diff --git a/subjects/atoi-exam/README.md b/subjects/atoi-exam/README.md
deleted file mode 100644
index 2ec461cc..00000000
--- a/subjects/atoi-exam/README.md
+++ /dev/null
@@ -1,59 +0,0 @@
-## atoi
-
-### Instructions
-
-- Write a function that simulates the behaviour of the `Atoi` function in Go. `Atoi` transforms a number represented as a `string` in a number represented as an `int`.
-
-- `Atoi` returns `0` if the `string` is not considered as a valid number. For this exercise **non-valid `string` chains will be tested**. Some will contain non-digits characters.
-
-- For this exercise the handling of the signs `+` or `-` **does have** to be taken into account.
-
-- This function will **only** have to return the `int`. For this exercise the `error` result of `Atoi` is not required.
-
-### Expected function
-
-```go
-func Atoi(s string) int {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	fmt.Println(Atoi("12345"))
-	fmt.Println(Atoi("0000000012345"))
-	fmt.Println(Atoi("012 345"))
-	fmt.Println(Atoi("Hello World!"))
-	fmt.Println(Atoi("+1234"))
-	fmt.Println(Atoi("-1234"))
-	fmt.Println(Atoi("++1234"))
-	fmt.Println(Atoi("--1234"))
-}
-```
-
-And its output :
-
-```console
-$ go run .
-12345
-12345
-0
-0
-1234
--1234
-0
-0
-$
-```
-
-### Notions
-
-- [strconv/Atoi](https://golang.org/pkg/strconv/#Atoi)
diff --git a/subjects/atoi/main.go b/subjects/atoi/main.go
new file mode 100644
index 00000000..ead6efe0
--- /dev/null
+++ b/subjects/atoi/main.go
@@ -0,0 +1,17 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.Atoi("12345"))
+	fmt.Println(piscine.Atoi("0000000012345"))
+	fmt.Println(piscine.Atoi("012 345"))
+	fmt.Println(piscine.Atoi("Hello World!"))
+	fmt.Println(piscine.Atoi("+1234"))
+	fmt.Println(piscine.Atoi("-1234"))
+	fmt.Println(piscine.Atoi("++1234"))
+	fmt.Println(piscine.Atoi("--1234"))
+}
diff --git a/subjects/atoibase-exam/README.md b/subjects/atoibase-exam/README.md
deleted file mode 100644
index 3b1159b6..00000000
--- a/subjects/atoibase-exam/README.md
+++ /dev/null
@@ -1,62 +0,0 @@
-## atoibase
-
-### Instructions
-
-Write a function that takes two arguments:
-
-- `s`: a numeric `string` in a given [base](<https://simple.wikipedia.org/wiki/Base_(mathematics)>).
-- `base`: a `string` representing all the different digits that can represent a numeric value.
-
-And return the integer value of `s` in the given `base`.
-
-If the base is not valid it returns `0`.
-
-Validity rules for a base :
-
-- A base must contain at least 2 characters.
-- Each character of a base must be unique.
-- A base should not contain `+` or `-` characters.
-
-String number must contain only elements that are in base.
-
-Only valid `string` numbers will be tested.
-
-The function **does not have** to manage negative numbers.
-
-### Expected function
-
-```go
-func AtoiBase(s string, base string) int {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	fmt.Println(AtoiBase("125", "0123456789"))
-	fmt.Println(AtoiBase("1111101", "01"))
-	fmt.Println(AtoiBase("7D", "0123456789ABCDEF"))
-	fmt.Println(AtoiBase("uoi", "choumi"))
-	fmt.Println(AtoiBase("bbbbbab", "-ab"))
-}
-```
-
-And its output :
-
-```console
-$ go run .
-125
-125
-125
-125
-0
-$
-```
diff --git a/subjects/atoibase/main.go b/subjects/atoibase/main.go
new file mode 100644
index 00000000..cb08409e
--- /dev/null
+++ b/subjects/atoibase/main.go
@@ -0,0 +1,14 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.AtoiBase("125", "0123456789"))
+	fmt.Println(piscine.AtoiBase("1111101", "01"))
+	fmt.Println(piscine.AtoiBase("7D", "0123456789ABCDEF"))
+	fmt.Println(piscine.AtoiBase("uoi", "choumi"))
+	fmt.Println(piscine.AtoiBase("bbbbbab", "-ab"))
+}
diff --git a/subjects/bezero/main.go b/subjects/bezero/main.go
new file mode 100644
index 00000000..78803a71
--- /dev/null
+++ b/subjects/bezero/main.go
@@ -0,0 +1,11 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.BeZero([]int{1, 2, 3, 4, 5, 6}))
+	fmt.Println(piscine.BeZero([]int{}))
+}
diff --git a/subjects/binarycheck/README.md b/subjects/binarycheck/README.md
index 1cb962e8..d1adba60 100644
--- a/subjects/binarycheck/README.md
+++ b/subjects/binarycheck/README.md
@@ -21,14 +21,15 @@ package main
 
 import (
     "fmt"
+    "piscine"
 )
 
 func main() {
-    fmt.Println(BinaryCheck(5))
-    fmt.Println(BinaryCheck(0))
-    fmt.Println(BinaryCheck(8))
-    fmt.Println(BinaryCheck(-9))
-    fmt.Println(BinaryCheck(-4))
+    fmt.Println(piscine.BinaryCheck(5))
+    fmt.Println(piscine.BinaryCheck(0))
+    fmt.Println(piscine.BinaryCheck(8))
+    fmt.Println(piscine.BinaryCheck(-9))
+    fmt.Println(piscine.BinaryCheck(-4))
 }
 ```
 
diff --git a/subjects/binarycheck/main.go b/subjects/binarycheck/main.go
new file mode 100644
index 00000000..2fac505f
--- /dev/null
+++ b/subjects/binarycheck/main.go
@@ -0,0 +1,14 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.BinaryCheck(5))
+	fmt.Println(piscine.BinaryCheck(0))
+	fmt.Println(piscine.BinaryCheck(8))
+	fmt.Println(piscine.BinaryCheck(-9))
+	fmt.Println(piscine.BinaryCheck(-4))
+}
diff --git a/subjects/compare-exam/README.md b/subjects/compare-exam/README.md
deleted file mode 100644
index c3432980..00000000
--- a/subjects/compare-exam/README.md
+++ /dev/null
@@ -1,43 +0,0 @@
-## compare
-
-### Instructions
-
-Write a function that behaves like the `Compare` function.
-
-### Expected function
-
-```go
-func Compare(a, b string) int {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	fmt.Println(Compare("Hello!", "Hello!"))
-	fmt.Println(Compare("Salut!", "lut!"))
-	fmt.Println(Compare("Ola!", "Ol"))
-}
-```
-
-And its output :
-
-```console
-$ go run .
-0
--1
-1
-$
-```
-
-### Notions
-
-- [strings/Compare](https://golang.org/pkg/strings/#Compare)
diff --git a/subjects/compare-exam/main.go b/subjects/compare-exam/main.go
deleted file mode 100644
index f6a1d3a8..00000000
--- a/subjects/compare-exam/main.go
+++ /dev/null
@@ -1,9 +0,0 @@
-package main
-
-import "fmt"
-
-func main() {
-	fmt.Println(Compare("Hello!", "Hello!"))
-	fmt.Println(Compare("Salut!", "lut!"))
-	fmt.Println(Compare("Ola!", "Ol"))
-}
diff --git a/subjects/compare/main.go b/subjects/compare/main.go
index 13a07476..fefd4ed4 100644
--- a/subjects/compare/main.go
+++ b/subjects/compare/main.go
@@ -2,10 +2,11 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(Compare("Hello!", "Hello!"))
-	fmt.Println(Compare("Salut!", "lut!"))
-	fmt.Println(Compare("Ola!", "Ol"))
+	fmt.Println(piscine.Compare("Hello!", "Hello!"))
+	fmt.Println(piscine.Compare("Salut!", "lut!"))
+	fmt.Println(piscine.Compare("Ola!", "Ol"))
 }
diff --git a/subjects/concatslice/README.md b/subjects/concatslice/README.md
index c902d486..96e15881 100644
--- a/subjects/concatslice/README.md
+++ b/subjects/concatslice/README.md
@@ -21,12 +21,13 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(ConcatSlice([]int{1, 2, 3}, []int{4, 5, 6}))
-	fmt.Println(ConcatSlice([]int{}, []int{4, 5, 6, 7, 8, 9}))
-	fmt.Println(ConcatSlice([]int{1, 2, 3}, []int{}))
+	fmt.Println(piscine.ConcatSlice([]int{1, 2, 3}, []int{4, 5, 6}))
+	fmt.Println(piscine.ConcatSlice([]int{}, []int{4, 5, 6, 7, 8, 9}))
+	fmt.Println(piscine.ConcatSlice([]int{1, 2, 3}, []int{}))
 }
 ```
 
diff --git a/subjects/concatslice/main.go b/subjects/concatslice/main.go
new file mode 100644
index 00000000..e7522cfa
--- /dev/null
+++ b/subjects/concatslice/main.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.ConcatSlice([]int{1, 2, 3}, []int{4, 5, 6}))
+	fmt.Println(piscine.ConcatSlice([]int{}, []int{4, 5, 6, 7, 8, 9}))
+	fmt.Println(piscine.ConcatSlice([]int{1, 2, 3}, []int{}))
+}
diff --git a/subjects/fifthandskip/README.md b/subjects/fifthandskip/README.md
index 334b47a8..6aa52e77 100644
--- a/subjects/fifthandskip/README.md
+++ b/subjects/fifthandskip/README.md
@@ -25,12 +25,13 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Print(FifthAndSkip("abcdefghijklmnopqrstuwxyz"))
-	fmt.Print(FifthAndSkip("This is a short sentence"))
-	fmt.Print(FifthAndSkip("1234"))
+	fmt.Print(piscine.FifthAndSkip("abcdefghijklmnopqrstuwxyz"))
+	fmt.Print(piscine.FifthAndSkip("This is a short sentence"))
+	fmt.Print(piscine.FifthAndSkip("1234"))
 }
 ```
 
diff --git a/subjects/fifthandskip/main.go b/subjects/fifthandskip/main.go
new file mode 100644
index 00000000..2adccff9
--- /dev/null
+++ b/subjects/fifthandskip/main.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Print(piscine.FifthAndSkip("abcdefghijklmnopqrstuwxyz"))
+	fmt.Print(piscine.FifthAndSkip("This is a short sentence"))
+	fmt.Print(piscine.FifthAndSkip("1234"))
+}
diff --git a/subjects/firstrune-exam/README.md b/subjects/firstrune-exam/README.md
deleted file mode 100644
index f2c7ef36..00000000
--- a/subjects/firstrune-exam/README.md
+++ /dev/null
@@ -1,44 +0,0 @@
-## firstrune
-
-### Instructions
-
-Write a function that returns the first `rune` of a `string`.
-
-### Expected function
-
-```go
-func FirstRune(s string) rune {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import (
-	"github.com/01-edu/z01"
-)
-
-func main() {
-	z01.PrintRune(FirstRune("Hello!"))
-	z01.PrintRune(FirstRune("Salut!"))
-	z01.PrintRune(FirstRune("Ola!"))
-	z01.PrintRune('\n')
-}
-```
-
-And its output :
-
-```console
-$ go run .
-HSO
-$
-```
-
-### Notions
-
-- [rune-literals](https://golang.org/ref/spec#Rune_literals)
diff --git a/subjects/firstrune/main.go b/subjects/firstrune/main.go
new file mode 100644
index 00000000..56dbc8b6
--- /dev/null
+++ b/subjects/firstrune/main.go
@@ -0,0 +1,14 @@
+package main
+
+import (
+	"github.com/01-edu/z01"
+
+	"piscine"
+)
+
+func main() {
+	z01.PrintRune(piscine.FirstRune("Hello!"))
+	z01.PrintRune(piscine.FirstRune("Salut!"))
+	z01.PrintRune(piscine.FirstRune("Ola!"))
+	z01.PrintRune('\n')
+}
diff --git a/subjects/fishandchips/README.md b/subjects/fishandchips/README.md
index e3da4781..c705ef81 100644
--- a/subjects/fishandchips/README.md
+++ b/subjects/fishandchips/README.md
@@ -27,12 +27,13 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(FishAndChips(4))
-	fmt.Println(FishAndChips(9))
-	fmt.Println(FishAndChips(6))
+	fmt.Println(piscine.FishAndChips(4))
+	fmt.Println(piscine.FishAndChips(9))
+	fmt.Println(piscine.FishAndChips(6))
 }
 ```
 
diff --git a/subjects/fishandchips/main.go b/subjects/fishandchips/main.go
new file mode 100644
index 00000000..3198319c
--- /dev/null
+++ b/subjects/fishandchips/main.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.FishAndChips(4))
+	fmt.Println(piscine.FishAndChips(9))
+	fmt.Println(piscine.FishAndChips(6))
+}
diff --git a/subjects/fromto/README.md b/subjects/fromto/README.md
index 0b9fc212..8d58ff64 100644
--- a/subjects/fromto/README.md
+++ b/subjects/fromto/README.md
@@ -26,13 +26,14 @@ package main
 
 import (
 	"fmt"
+	"psicine"
 )
 
 func main() {
-	fmt.Print(FromTo(1, 10))
-	fmt.Print(FromTo(10, 1))
-	fmt.Print(FromTo(10, 10))
-	fmt.Print(FromTo(100, 10))
+	fmt.Print(piscine.FromTo(1, 10))
+	fmt.Print(piscine.FromTo(10, 1))
+	fmt.Print(piscine.FromTo(10, 10))
+	fmt.Print(piscine.FromTo(100, 10))
 }
 ```
 
diff --git a/subjects/fromto/main.go b/subjects/fromto/main.go
new file mode 100644
index 00000000..3cc0133a
--- /dev/null
+++ b/subjects/fromto/main.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"fmt"
+)
+
+func main() {
+	fmt.Print(piscine.FromTo(1, 10))
+	fmt.Print(piscine.FromTo(10, 1))
+	fmt.Print(piscine.FromTo(10, 10))
+	fmt.Print(piscine.FromTo(100, 10))
+}
diff --git a/subjects/issorted/main.go b/subjects/issorted/main.go
index e08dc27c..e881d148 100644
--- a/subjects/issorted/main.go
+++ b/subjects/issorted/main.go
@@ -2,14 +2,15 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
 	a1 := []int{0, 1, 2, 3, 4, 5}
 	a2 := []int{0, 2, 1, 3}
 
-	result1 := IsSorted(f, a1)
-	result2 := IsSorted(f, a2)
+	result1 := piscine.IsSorted(f, a1)
+	result2 := piscine.IsSorted(f, a2)
 
 	fmt.Println(result1)
 	fmt.Println(result2)
diff --git a/subjects/lastrune-exam/README.md b/subjects/lastrune-exam/README.md
deleted file mode 100644
index 45c82d61..00000000
--- a/subjects/lastrune-exam/README.md
+++ /dev/null
@@ -1,44 +0,0 @@
-## lastrune
-
-### Instructions
-
-Write a function that returns the last `rune` of a `string`.
-
-### Expected function
-
-```go
-func LastRune(s string) rune {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import (
-	"github.com/01-edu/z01"
-)
-
-func main() {
-	z01.PrintRune(LastRune("Hello!"))
-	z01.PrintRune(LastRune("Salut!"))
-	z01.PrintRune(LastRune("Ola!"))
-	z01.PrintRune('\n')
-}
-```
-
-And its output :
-
-```console
-$ go run .
-!!!
-$
-```
-
-### Notions
-
-- [rune-literals](https://golang.org/ref/spec#Rune_literals)
diff --git a/subjects/lastrune/main.go b/subjects/lastrune/main.go
new file mode 100644
index 00000000..fc91c549
--- /dev/null
+++ b/subjects/lastrune/main.go
@@ -0,0 +1,14 @@
+package main
+
+import (
+	"github.com/01-edu/z01"
+
+	"piscine"
+)
+
+func main() {
+	z01.PrintRune(piscine.LastRune("Hello!"))
+	z01.PrintRune(piscine.LastRune("Salut!"))
+	z01.PrintRune(piscine.LastRune("Ola!"))
+	z01.PrintRune('\n')
+}
diff --git a/subjects/listremoveif-exam/README.md b/subjects/listremoveif-exam/README.md
deleted file mode 100644
index 6d225485..00000000
--- a/subjects/listremoveif-exam/README.md
+++ /dev/null
@@ -1,102 +0,0 @@
-## listremoveif
-
-### Instructions
-
-Write a function `ListRemoveIf` that removes all elements that are equal to the `data_ref` in the argument of the function.
-
-### Expected function and structure
-
-```go
-type NodeL struct {
-	Data interface{}
-	Next *NodeL
-}
-
-type List struct {
-	Head *NodeL
-	Tail *NodeL
-}
-
-func ListRemoveIf(l *List, data_ref interface{}) {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func PrintList(l *List) {
-	it := l.Head
-	for it != nil {
-		fmt.Print(it.Data, " -> ")
-		it = it.Next
-	}
-
-	fmt.Print(nil, "\n")
-}
-
-func main() {
-	link := &List{}
-	link2 := &List{}
-
-	fmt.Println("----normal state----")
-	ListPushBack(link2, 1)
-	PrintList(link2)
-	ListRemoveIf(link2, 1)
-	fmt.Println("------answer-----")
-	PrintList(link2)
-	fmt.Println()
-
-	fmt.Println("----normal state----")
-	ListPushBack(link, 1)
-	ListPushBack(link, "Hello")
-	ListPushBack(link, 1)
-	ListPushBack(link, "There")
-	ListPushBack(link, 1)
-	ListPushBack(link, 1)
-	ListPushBack(link, "How")
-	ListPushBack(link, 1)
-	ListPushBack(link, "are")
-	ListPushBack(link, "you")
-	ListPushBack(link, 1)
-	PrintList(link)
-
-	ListRemoveIf(link, 1)
-	fmt.Println("------answer-----")
-	PrintList(link)
-}
-
-func ListPushBack(l *List, data interface{}) {
-	n := &NodeL{Data: data}
-	if l.Head == nil {
-		l.Head = n
-		l.Tail = n
-	} else {
-		l.Tail.Next = n
-		l.Tail = n
-	}
-}
-
-```
-
-And its output :
-
-```console
-$ go run .
-----normal state----
-1 -> <nil>
-------answer-----
-<nil>
-
-----normal state----
-1 -> Hello -> 1 -> There -> 1 -> 1 -> How -> 1 -> are -> you -> 1 -> <nil>
-------answer-----
-Hello -> There -> How -> are -> you -> <nil>
-$
-```
diff --git a/subjects/listremoveif-exam/main.go b/subjects/listremoveif-exam/main.go
deleted file mode 100644
index 920a58db..00000000
--- a/subjects/listremoveif-exam/main.go
+++ /dev/null
@@ -1,55 +0,0 @@
-package main
-
-import "fmt"
-
-func PrintList(l *List) {
-	it := l.Head
-	for it != nil {
-		fmt.Print(it.Data, " -> ")
-		it = it.Next
-	}
-
-	fmt.Print(nil, "\n")
-}
-
-func main() {
-	link := &List{}
-	link2 := &List{}
-
-	fmt.Println("----normal state----")
-	ListPushBack(link2, 1)
-	PrintList(link2)
-	ListRemoveIf(link2, 1)
-	fmt.Println("------answer-----")
-	PrintList(link2)
-	fmt.Println()
-
-	fmt.Println("----normal state----")
-	ListPushBack(link, 1)
-	ListPushBack(link, "Hello")
-	ListPushBack(link, 1)
-	ListPushBack(link, "There")
-	ListPushBack(link, 1)
-	ListPushBack(link, 1)
-	ListPushBack(link, "How")
-	ListPushBack(link, 1)
-	ListPushBack(link, "are")
-	ListPushBack(link, "you")
-	ListPushBack(link, 1)
-	PrintList(link)
-
-	ListRemoveIf(link, 1)
-	fmt.Println("------answer-----")
-	PrintList(link)
-}
-
-func ListPushBack(l *List, data interface{}) {
-	n := &NodeL{Data: data}
-	if l.Head == nil {
-		l.Head = n
-		l.Tail = n
-	} else {
-		l.Tail.Next = n
-		l.Tail = n
-	}
-}
diff --git a/subjects/max-exam/README.md b/subjects/max-exam/README.md
deleted file mode 100644
index 361f10a4..00000000
--- a/subjects/max-exam/README.md
+++ /dev/null
@@ -1,37 +0,0 @@
-## max
-
-### Instructions
-
-Write a function `Max` that will return the maximum value in a slice of integers. If the slice is empty it will return 0.
-
-### Expected function
-
-```go
-func Max(a []int) int {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	a := []int{23, 123, 1, 11, 55, 93}
-	max := Max(a)
-	fmt.Println(max)
-}
-```
-
-And its output :
-
-```console
-$ go run .
-123
-$
-```
diff --git a/subjects/max/main.go b/subjects/max/main.go
new file mode 100644
index 00000000..225d71de
--- /dev/null
+++ b/subjects/max/main.go
@@ -0,0 +1,12 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	a := []int{23, 123, 1, 11, 55, 93}
+	max := piscine.Max(a)
+	fmt.Println(max)
+}
diff --git a/subjects/printcomb-exam/README.md b/subjects/printcomb-exam/README.md
deleted file mode 100644
index 48644347..00000000
--- a/subjects/printcomb-exam/README.md
+++ /dev/null
@@ -1,43 +0,0 @@
-## printcomb
-
-### Instructions
-
-Write a function that prints, in ascending order and on a single line: all **unique** combinations of three different digits so that, the first digit is lower than the second, and the second is lower than the third.
-
-These combinations are separated by a comma and a space.
-
-### Expected function
-
-```go
-func PrintComb() {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-func main() {
-	PrintComb()
-}
-```
-
-This is the incomplete output :
-
-```console
-$ go run . | cat -e
-012, 013, 014, 015, 016, 017, 018, 019, 023, ..., 689, 789$
-$
-```
-
-- `000` or `999` are not valid combinations because the digits are not different.
-
-- `987` should not be shown because the first digit is not less than the second.
-
-### Notions
-
-- [01-edu/z01](https://github.com/01-edu/z01)
diff --git a/subjects/printcomb/main.go b/subjects/printcomb/main.go
new file mode 100644
index 00000000..10670967
--- /dev/null
+++ b/subjects/printcomb/main.go
@@ -0,0 +1,7 @@
+package main
+
+import "piscine"
+
+func main() {
+	piscine.PrintComb()
+}
diff --git a/subjects/printmemory/README.md b/subjects/printmemory/README.md
index 8926a49b..bcea4043 100644
--- a/subjects/printmemory/README.md
+++ b/subjects/printmemory/README.md
@@ -23,8 +23,10 @@ Here is a possible program to test your function :
 ```go
 package main
 
+import "piscine"
+
 func main() {
-	PrintMemory([10]byte{'h', 'e', 'l', 'l', 'o', 16, 21, '*'})
+	piscine.PrintMemory([10]byte{'h', 'e', 'l', 'l', 'o', 16, 21, '*'})
 }
 ```
 
diff --git a/subjects/printmemory/main.go b/subjects/printmemory/main.go
new file mode 100644
index 00000000..4dfc3559
--- /dev/null
+++ b/subjects/printmemory/main.go
@@ -0,0 +1,7 @@
+package main
+
+import "piscine"
+
+func main() {
+	piscine.PrintMemory([10]byte{'h', 'e', 'l', 'l', 'o', 16, 21, '*'})
+}
diff --git a/subjects/retainfirsthalf/README.md b/subjects/retainfirsthalf/README.md
index 65de86e8..df0b42a4 100644
--- a/subjects/retainfirsthalf/README.md
+++ b/subjects/retainfirsthalf/README.md
@@ -25,13 +25,14 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(RetainFirstHalf("This is the 1st halfThis is the 2nd half"))
-	fmt.Println(RetainFirstHalf("A"))
-	fmt.Println(RetainFirstHalf(""))
-	fmt.Println(RetainFirstHalf("Hello World"))
+	fmt.Println(piscine.RetainFirstHalf("This is the 1st halfThis is the 2nd half"))
+	fmt.Println(piscine.RetainFirstHalf("A"))
+	fmt.Println(piscine.RetainFirstHalf(""))
+	fmt.Println(piscine.RetainFirstHalf("Hello World"))
 }
 ```
 
diff --git a/subjects/retainfirsthalf/main.go b/subjects/retainfirsthalf/main.go
new file mode 100644
index 00000000..1ddf21f9
--- /dev/null
+++ b/subjects/retainfirsthalf/main.go
@@ -0,0 +1,13 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.RetainFirstHalf("This is the 1st halfThis is the 2nd half"))
+	fmt.Println(piscine.RetainFirstHalf("A"))
+	fmt.Println(piscine.RetainFirstHalf(""))
+	fmt.Println(piscine.RetainFirstHalf("Hello World"))
+}
diff --git a/subjects/revconcatalternate/README.md b/subjects/revconcatalternate/README.md
index c1547ee9..6fcad74f 100644
--- a/subjects/revconcatalternate/README.md
+++ b/subjects/revconcatalternate/README.md
@@ -27,13 +27,14 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(RevConcatAlternate([]int{1, 2, 3}, []int{4, 5, 6}))
-	fmt.Println(RevConcatAlternate([]int{1, 2, 3}, []int{4, 5, 6, 7, 8, 9}))
-	fmt.Println(RevConcatAlternate([]int{1, 2, 3, 9, 8}, []int{4, 5}))
-	fmt.Println(RevConcatAlternate([]int{1, 2, 3}, []int{}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{4, 5, 6}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{4, 5, 6, 7, 8, 9}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3, 9, 8}, []int{4, 5}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{}))
 }
 ```
 
diff --git a/subjects/revconcatalternate/main.go b/subjects/revconcatalternate/main.go
new file mode 100644
index 00000000..366578ca
--- /dev/null
+++ b/subjects/revconcatalternate/main.go
@@ -0,0 +1,13 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{4, 5, 6}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{4, 5, 6, 7, 8, 9}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3, 9, 8}, []int{4, 5}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{}))
+}
diff --git a/subjects/rot14-exam/README.md b/subjects/rot14-exam/README.md
deleted file mode 100644
index 8063328b..00000000
--- a/subjects/rot14-exam/README.md
+++ /dev/null
@@ -1,45 +0,0 @@
-## rot14
-
-### Instructions
-
-Write a function `rot14` that returns the `string` within the parameter transformed into a `rot14 string`.
-Each letter will be replaced by the letter 14 spots ahead in the alphabetical order.
-
-- 'z' becomes 'n' and 'Z' becomes 'N'. The case of the letter stays the same.
-
-### Expected function
-
-```go
-func Rot14(s string) string {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import (
-	"github.com/01-edu/z01"
-)
-
-func main() {
-	result := Rot14("Hello! How are You?")
-
-	for _, r := range result {
-		z01.PrintRune(r)
-	}
-	z01.PrintRune('\n')
-}
-```
-
-And its output :
-
-```console
-$ go run .
-Vszzc! Vck ofs Mci?
-$
-```
diff --git a/subjects/rot14/main.go b/subjects/rot14/main.go
new file mode 100644
index 00000000..775d0dc2
--- /dev/null
+++ b/subjects/rot14/main.go
@@ -0,0 +1,16 @@
+package main
+
+import (
+	"piscine"
+
+	"github.com/01-edu/z01"
+)
+
+func main() {
+	result := piscine.Rot14("Hello! How are You?")
+
+	for _, r := range result {
+		z01.PrintRune(r)
+	}
+	z01.PrintRune('\n')
+}
diff --git a/subjects/saveandmiss/README.md b/subjects/saveandmiss/README.md
index 483f31c2..b96c6781 100644
--- a/subjects/saveandmiss/README.md
+++ b/subjects/saveandmiss/README.md
@@ -23,15 +23,16 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(SaveAndMiss("123456789", 3))
-	fmt.Println(SaveAndMiss("abcdefghijklmnopqrstuvwyz", 3))
-	fmt.Println(SaveAndMiss("", 3))
-	fmt.Println(SaveAndMiss("hello you all ! ", 0))
-	fmt.Println(SaveAndMiss("what is your name?", 0))
-	fmt.Println(SaveAndMiss("go Exercise Save and Miss", -5))
+	fmt.Println(piscine.SaveAndMiss("123456789", 3))
+	fmt.Println(piscine.SaveAndMiss("abcdefghijklmnopqrstuvwyz", 3))
+	fmt.Println(piscine.SaveAndMiss("", 3))
+	fmt.Println(piscine.SaveAndMiss("hello you all ! ", 0))
+	fmt.Println(piscine.SaveAndMiss("what is your name?", 0))
+	fmt.Println(piscine.SaveAndMiss("go Exercise Save and Miss", -5))
 }
 ```
 
diff --git a/subjects/saveandmiss/main.go b/subjects/saveandmiss/main.go
new file mode 100644
index 00000000..f9380216
--- /dev/null
+++ b/subjects/saveandmiss/main.go
@@ -0,0 +1,15 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Println(piscine.SaveAndMiss("123456789", 3))
+	fmt.Println(piscine.SaveAndMiss("abcdefghijklmnopqrstuvwyz", 3))
+	fmt.Println(piscine.SaveAndMiss("", 3))
+	fmt.Println(piscine.SaveAndMiss("hello you all ! ", 0))
+	fmt.Println(piscine.SaveAndMiss("what is your name?", 0))
+	fmt.Println(piscine.SaveAndMiss("go Exercise Save and Miss", -5))
+}
diff --git a/subjects/setspace/main.go b/subjects/setspace/main.go
index 1a9481db..0fee7980 100644
--- a/subjects/setspace/main.go
+++ b/subjects/setspace/main.go
@@ -2,12 +2,13 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(SetSpace("HelloWorld"))
-	fmt.Println(SetSpace("HelloWorld12"))
-	fmt.Println(SetSpace("Hello World"))
-	fmt.Println(SetSpace(""))
-	fmt.Println(SetSpace("LoremIpsumWord"))
+	fmt.Println(piscine.SetSpace("HelloWorld"))
+	fmt.Println(piscine.SetSpace("HelloWorld12"))
+	fmt.Println(piscine.SetSpace("Hello World"))
+	fmt.Println(piscine.SetSpace(""))
+	fmt.Println(piscine.SetSpace("LoremIpsumWord"))
 }
diff --git a/subjects/slice/README.md b/subjects/slice/README.md
index 70722ca8..5d2f2ae8 100644
--- a/subjects/slice/README.md
+++ b/subjects/slice/README.md
@@ -23,15 +23,18 @@ Here is a possible program to test your function :
 ```go
 package main
 
-import "fmt"
+import (
+    "fmt"
+    "piscine"
+)
 
 func main(){
     a := []string{"coding", "algorithm", "ascii", "package", "golang"}
-    fmt.Printf("%#v\n", Slice(a, 1))
-    fmt.Printf("%#v\n", Slice(a, 2, 4))
-    fmt.Printf("%#v\n", Slice(a, -3))
-    fmt.Printf("%#v\n", Slice(a, -2, -1))
-    fmt.Printf("%#v\n", Slice(a, 2, 0))
+    fmt.Printf("%#v\n", piscine.Slice(a, 1))
+    fmt.Printf("%#v\n", piscine.Slice(a, 2, 4))
+    fmt.Printf("%#v\n", piscine.Slice(a, -3))
+    fmt.Printf("%#v\n", piscine.Slice(a, -2, -1))
+    fmt.Printf("%#v\n", piscine.Slice(a, 2, 0))
 }
 ```
 
diff --git a/subjects/slice/main.go b/subjects/slice/main.go
new file mode 100644
index 00000000..df4aedf4
--- /dev/null
+++ b/subjects/slice/main.go
@@ -0,0 +1,15 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	a := []string{"coding", "algorithm", "ascii", "package", "golang"}
+	fmt.Printf("%#v\n", piscine.Slice(a, 1))
+	fmt.Printf("%#v\n", piscine.Slice(a, 2, 4))
+	fmt.Printf("%#v\n", piscine.Slice(a, -3))
+	fmt.Printf("%#v\n", piscine.Slice(a, -2, -1))
+	fmt.Printf("%#v\n", piscine.Slice(a, 2, 0))
+}
diff --git a/subjects/sliceadd/main.go b/subjects/sliceadd/main.go
index 2a2d18f7..f3c8dd7d 100644
--- a/subjects/sliceadd/main.go
+++ b/subjects/sliceadd/main.go
@@ -2,9 +2,10 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(SliceAdd([]int{1, 2, 3}, 4))
-	fmt.Println(SliceAdd([]int{}, 4))
+	fmt.Println(piscine.SliceAdd([]int{1, 2, 3}, 4))
+	fmt.Println(piscine.SliceAdd([]int{}, 4))
 }
diff --git a/subjects/sliceremove/main.go b/subjects/sliceremove/main.go
index cf856839..2cf56bc4 100644
--- a/subjects/sliceremove/main.go
+++ b/subjects/sliceremove/main.go
@@ -2,11 +2,12 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(SliceRemove([]int{1, 2, 3}, 2))
-	fmt.Println(SliceRemove([]int{4, 3}, 4))
-	fmt.Println(SliceRemove([]int{}, 1))
+	fmt.Println(piscine.SliceRemove([]int{1, 2, 3}, 2))
+	fmt.Println(piscine.SliceRemove([]int{4, 3}, 4))
+	fmt.Println(piscine.SliceRemove([]int{}, 1))
 
 }
diff --git a/subjects/sortwordarr-exam/README.md b/subjects/sortwordarr-exam/README.md
deleted file mode 100644
index edb60be3..00000000
--- a/subjects/sortwordarr-exam/README.md
+++ /dev/null
@@ -1,38 +0,0 @@
-## sortwordarr
-
-### Instructions
-
-Write a function `SortWordArr` that sorts by `ascii` (in ascending order) a `string` slice.
-
-### Expected function
-
-```go
-func SortWordArr(a []string) {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	result := []string{"a", "A", "1", "b", "B", "2", "c", "C", "3"}
-	SortWordArr(result)
-
-	fmt.Println(result)
-}
-```
-
-And its output :
-
-```console
-$ go run .
-[1 2 3 A B C a b c]
-$
-```
diff --git a/subjects/sortwordarr-exam/main.go b/subjects/sortwordarr-exam/main.go
deleted file mode 100644
index 603daecf..00000000
--- a/subjects/sortwordarr-exam/main.go
+++ /dev/null
@@ -1,9 +0,0 @@
-package main
-
-import "fmt"
-
-func main() {
-	result := []string{"a", "A", "1", "b", "B", "2", "c", "C", "3"}
-	SortWordArr(result)
-	fmt.Println(result)
-}
diff --git a/subjects/split-exam/README.md b/subjects/split-exam/README.md
deleted file mode 100644
index 4773c4d3..00000000
--- a/subjects/split-exam/README.md
+++ /dev/null
@@ -1,36 +0,0 @@
-## split
-
-### Instructions
-
-Write a function that receives a string and a separator and returns a `slice of strings` that results of splitting the string `s` by the separator `sep`.
-
-### Expected function
-
-```go
-func Split(s, sep string) []string {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	s := "HelloHAhowHAareHAyou?"
-	fmt.Printf("%#v\n", Split(s, "HA"))
-}
-```
-
-And its output :
-
-```console
-$ go run .
-[]string{"Hello", "how", "are", "you?"}
-$
-```
diff --git a/subjects/split/main.go b/subjects/split/main.go
new file mode 100644
index 00000000..aec24cec
--- /dev/null
+++ b/subjects/split/main.go
@@ -0,0 +1,11 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	s := "HelloHAhowHAareHAyou?"
+	fmt.Printf("%#v\n", piscine.Split(s, "HA"))
+}
diff --git a/subjects/strlen-exam/README.md b/subjects/strlen-exam/README.md
deleted file mode 100644
index 692209af..00000000
--- a/subjects/strlen-exam/README.md
+++ /dev/null
@@ -1,36 +0,0 @@
-## strlen
-
-### Instructions
-
-- Write a function that counts the `runes` of a `string` and that returns that count.
-
-### Expected function
-
-```go
-func StrLen(s string) int {
-
-}
-```
-
-### Usage
-
-Here is a possible program to test your function :
-
-```go
-package main
-
-import "fmt"
-
-func main() {
-	l := StrLen("Hello World!")
-	fmt.Println(l)
-}
-```
-
-And its output :
-
-```console
-$ go run .
-12
-$
-```
diff --git a/subjects/strlen/main.go b/subjects/strlen/main.go
new file mode 100644
index 00000000..2de750f6
--- /dev/null
+++ b/subjects/strlen/main.go
@@ -0,0 +1,11 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	l := piscine.StrLen("Hello World!")
+	fmt.Println(l)
+}
diff --git a/subjects/wordflip/README.md b/subjects/wordflip/README.md
index 78d0c154..5186bca0 100644
--- a/subjects/wordflip/README.md
+++ b/subjects/wordflip/README.md
@@ -25,13 +25,14 @@ package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Print(WordFlip("First second last"))
-	fmt.Print(WordFlip(""))
-	fmt.Print(WordFlip("     "))
-	fmt.Print(WordFlip(" hello  all  of  you! "))
+	fmt.Print(piscine.WordFlip("First second last"))
+	fmt.Print(piscine.WordFlip(""))
+	fmt.Print(piscine.WordFlip("     "))
+	fmt.Print(piscine.WordFlip(" hello  all  of  you! "))
 }
 ```
 
diff --git a/subjects/wordflip/main.go b/subjects/wordflip/main.go
new file mode 100644
index 00000000..fff73800
--- /dev/null
+++ b/subjects/wordflip/main.go
@@ -0,0 +1,13 @@
+package main
+
+import (
+	"fmt"
+	"piscine"
+)
+
+func main() {
+	fmt.Print(piscine.WordFlip("First second last"))
+	fmt.Print(piscine.WordFlip(""))
+	fmt.Print(piscine.WordFlip("     "))
+	fmt.Print(piscine.WordFlip(" hello  all  of  you! "))
+}