22 KiB
go-reloaded
Introduction
- Welcome back. Congratulations on your admission.
This subject is a selection of the best exercises of the piscine-go. This selection was made to get back smoothly to programming in go after the pause period. All the exercises have to be done and they must all pass each and every tests.
The goal of this project is to realize what you know and what you still need to practice on. We strongly advise you to resist the temptation of looking at your old repository.
To really learn programming, you must practice programming, so copy and pasting some old code will not help the learning process.
One more detail. This time the project will be corrected by auditors. The auditors will be others students and you will be an auditor as well.
We advise you to create your own tests for yourself and for when you will correct your students.
atoi
Allowed functions
"--cast"
Instructions
-
Write a function that simulates the behaviour of the
Atoi
function in Go.Atoi
transforms a number represented as astring
in a number represented as anint
. -
Atoi
returns0
if thestring
is not considered as a valid number. For this exercise non-validstring
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 theerror
result of atoi is not required.
Expected function
func Atoi(s string) int {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
fmt.Println(student.Atoi("12345"))
fmt.Println(student.Atoi("0000000012345"))
fmt.Println(student.Atoi("012 345"))
fmt.Println(student.Atoi("Hello World!"))
fmt.Println(student.Atoi("+1234"))
fmt.Println(student.Atoi("-1234"))
fmt.Println(student.Atoi("++1234"))
fmt.Println(student.Atoi("--1234"))
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
12345
12345
0
0
1234
-1234
0
0
student@ubuntu:~/[[ROOT]]/test$
recursivepower
Allowed functions
"--cast"
Instructions
Write an recursive function that returns the power of the int
passed as parameter.
Negative powers will return 0
. Overflows do not have to be dealt with.
for
is forbidden for this exercise.
Expected function
func RecursivePower(nb int, power int) int {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
arg1 := 4
arg2 := 3
fmt.Println(student.RecursivePower(arg1, arg2))
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
64
student@ubuntu:~/[[ROOT]]/test$
printcombn
Allowed functions
"--cast"
"github.com/01-edu/z01.PrintRune"
Instructions
-
Write a function that prints all possible combinations of n different digits in ascending order.
-
n will be defined as : 0 < n < 10
below are your references for the printing format expected.
-
(for n = 1) '0, 1, 2, 3, ...8, 9'
-
(for n = 3) '012, 013, 014, 015, 016, 017, 018, 019, 023,...689, 789'
Expected function
func PrintCombN(n int) {
}
Usage
Here is a possible program to test your function :
package main
import student ".."
func main() {
student.PrintCombN(1)
student.PrintCombN(3)
student.PrintCombN(9)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
0, 1, 2, 3, 4, 5, 6, 7, 8, 9
012, 013, 014, 015, 016, 017, 018, ... 679, 689, 789
012345678, 012345679, ..., 123456789
student@ubuntu:~/[[ROOT]]/test$
printnbrbase
Allowed functions
"--cast"
"github.com/01-edu/z01.PrintRune"
Instructions
Write a function that prints an int
in a string
base passed in parameters.
If the base is not valid, the function prints NV
(Not Valid):
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.
The function has to manage negative numbers. (as shown in the example)
Expected function
func PrintNbrBase(nbr int, base string) {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
"github.com/01-edu/z01"
student ".."
)
func main() {
student.PrintNbrBase(125, "0123456789")
z01.PrintRune('\n')
student.PrintNbrBase(-125, "01")
z01.PrintRune('\n')
student.PrintNbrBase(125, "0123456789ABCDEF")
z01.PrintRune('\n')
student.PrintNbrBase(-125, "choumi")
z01.PrintRune('\n')
student.PrintNbrBase(125, "aa")
z01.PrintRune('\n')
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
125
-1111101
7D
-uoi
NV
student@ubuntu:~/[[ROOT]]/test$
doop
Allowed functions
"--cast"
"github.com/01-edu/z01.PrintRune"
"os.*"
".."
Instructions
Write a program that is called doop
.
The program has to be used with three arguments:
- A value
- An operator
- Another value
You should use int64
.
The following operators are considered valid: +
, -
, /
, *
, %
.
In case of an invalid operator or overflow the programs prints 0
.
In case of an invalid number of arguments the program prints nothing.
The program has to handle the modulo and division operations by 0 as shown on the output examples below.
Usage
student@ubuntu:~/[[ROOT]]/test$ go build doop.go
student@ubuntu:~/[[ROOT]]/test$ ./doop
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 + 1 | cat -e
2$
student@ubuntu:~/[[ROOT]]/test$ ./doop hello + 1 | cat -e
0$
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 p 1 | cat -e
0$
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 / 0 | cat -e
No division by 0$
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 % 0 | cat -e
No modulo by 0$
student@ubuntu:~/[[ROOT]]/test$ ./doop 9223372036854775807 + 1
0
student@ubuntu:~/[[ROOT]]/test$ ./doop -9223372036854775809 - 3
0
student@ubuntu:~/[[ROOT]]/test$ ./doop 9223372036854775807 "*" 3
0
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 "*" 1
1
student@ubuntu:~/[[ROOT]]/test$ ./doop 1 "*" -1
-1
student@ubuntu:~/[[ROOT]]/test$
atoibase
Allowed functions
"--cast"
"make"
Instructions
Write a function that takes a string
number and its string
base in parameters and returns its conversion as an int
.
If the base or the string
number 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.
Only valid string
numbers will be tested.
The function does not have to manage negative numbers.
Expected function
func AtoiBase(s string, base string) int {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
fmt.Println(student.AtoiBase("125", "0123456789"))
fmt.Println(student.AtoiBase("1111101", "01"))
fmt.Println(student.AtoiBase("7D", "0123456789ABCDEF"))
fmt.Println(student.AtoiBase("uoi", "choumi"))
fmt.Println(student.AtoiBase("bbbbbab", "-ab"))
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
125
125
125
125
0
student@ubuntu:~/[[ROOT]]/test$
splitwhitespaces
Allowed functions
"--cast"
"make"
Instructions
Write a function that separates the words of a string
and puts them in a string
slice.
The separators are spaces, tabs and newlines.
Expected function
func SplitWhiteSpaces(s string) []string {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
fmt.Println(student.SplitWhiteSpaces("Hello how are you?"))
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
[Hello how are you?]
student@ubuntu:~/[[ROOT]]/test$
split
Allowed functions
"--cast"
"make"
Instructions
Write a function that simulates the behaviour of the strings.Split
function in Go. strings.Split
separates the words of a string
and puts them in a string
slice.
The separators are the characters of the separator string given in parameter.
Expected function
func Split(s, sep string) []string {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
s := "HelloHAhowHAareHAyou?"
fmt.Println(student.Split(s, "HA"))
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
[Hello how are you?]
student@ubuntu:~/[[ROOT]]/test$
convertbase
Allowed functions
"--cast"
".."
Instructions
Write a function that returns the conversion of a string
number from one string
baseFrom to one string
baseTo.
Only valid bases will be tested.
Negative numbers will not be tested.
Expected function
func ConvertBase(nbr, baseFrom, baseTo string) string {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
result := student.ConvertBase("101011", "01", "0123456789")
fmt.Println(result)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
43
student@ubuntu:~/[[ROOT]]/test$
rotatevowels
Allowed functions
"os.*"
"--cast"
"github.com/01-edu/z01.PrintRune"
"make"
Instructions
Write a program that checks the arguments for vowels.
- If the argument contains vowels (for this exercise
y
is not considered a vowel) the program has to "mirror" the position of the vowels in the argument (see the examples). - If the number of arguments is less than 1, the program display a new line ("
\n
"). - If the arguments does not have any vowels, the program just prints the arguments.
Example of output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./rotatevowels "Hello World" | cat -e
Hollo Werld$
student@ubuntu:~/[[ROOT]]/test$ ./rotatevowels "HEllO World" "problem solved"
Hello Werld problom sOlvEd
student@ubuntu:~/[[ROOT]]/test$ ./rotatevowels "str" "shh" "psst"
str shh psst
student@ubuntu:~/[[ROOT]]/test$ ./rotatevowels "happy thoughts" "good luck"
huppy thooghts guod lack
student@ubuntu:~/[[ROOT]]/test$ ./rotatevowels "aEi" "Ou"
uOi Ea
student@ubuntu:~/[[ROOT]]/test$ ./rotatevowels
student@ubuntu:~/[[ROOT]]/test$
advancedsortwordarr
Allowed functions
".."
"len"
Instructions
Write a function AdvancedSortWordArr
that sorts a string
slice, based on the function f
passed in parameter.
Expected function
func AdvancedSortWordArr(a []string, f func(a, b string) int) {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
result := []string{"a", "A", "1", "b", "B", "2", "c", "C", "3"}
student.AdvancedSortWordArr(result, student.Compare)
fmt.Println(result)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
[1 2 3 A B C a b c]
student@ubuntu:~/[[ROOT]]/test$
cat
Allowed functions
"os.*"
"--cast"
"github.com/01-edu/z01.PrintRune"
".."
"ioutil.*"
"io.*"
Instructions
Write a program that has the same behaviour as the system's cat
command-line.
-
The
options
do not have to be handled. -
If the program is called without arguments it should take the
input
and print it back (as shown with the "Hello" example below). -
In the program folder create two files named
quest8.txt
andquest8T.txt
. -
Copy to the
quest8.txt
file the following sentence :
"Programming is a skill best acquired by practice and example rather than from books" by Alan Turing
- Copy to the
quest8T.txt
file the following sentence :
"Alan Mathison Turing was an English mathematician, computer scientist, logician, cryptanalyst. Turing was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. Turing is widely considered to be the father of theoretical computer science and artificial intelligence."
-
In case of error the program should print the error.
-
The program must be submitted inside a folder named
cat
.
student@ubuntu:~/[[ROOT]]/cat$ go build
student@ubuntu:~/[[ROOT]]/cat$ ./cat abc
open abc: no such file or directory
student@ubuntu:~/[[ROOT]]/cat$ ./cat quest8.txt
"Programming is a skill best acquired by pratice and example rather than from books" by Alan Turing
student@ubuntu:~/[[ROOT]]/cat$ ./cat
Hello
Hello
^C
student@ubuntu:~/[[ROOT]]/cat$ ./cat quest8.txt quest8T.txt
"Programming is a skill best acquired by pratice and example rather than from books" by Alan Turing
"Alan Mathison Turing was an English mathematician, computer scientist, logician, cryptanalyst. Turing was highly influential in the development of theoretical computer science, providing a formalisation of the concepts of algorithm and computation with the Turing machine, which can be considered a model of a general-purpose computer. Turing is widely considered to be the father of theoretical computer science and artificial intelligence."
student@ubuntu:~/[[ROOT]]/cat$
ztail
Allowed functions
"os.*"
"--cast"
"github.com/01-edu/z01.PrintRune"
"append"
"fmt.Printf"
".."
Instructions
Write a program called ztail
that has the same behaviour as the system command tail
, but which takes at least one file as argument.
-
The only option to be handled is
-c
. This option will be used in all tests. -
For this program the "os" package can be used.
-
For the program to pass the tests the convention for the return code of program in Unix systems should be followed.
-
Handle the errors and output the same error messages as
tail
. -
For more information consult the man page for
tail
.
Note:
This program is gonna be tested against tail
, be sure to check all the different error messages with different permutations of the arguments.
activebits
Allowed functions
"--cast"
Instructions
Write a function, ActiveBits
, that returns the number of active bits
(bits with the value 1) in the binary representation of an integer number.
Expected function
func ActiveBits(n int) uint {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
nbits := student.ActiveBits(7)
fmt.Println(nbits)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
3
student@ubuntu:~/[[ROOT]]/test$
sortlistinsert
Allowed functions
"--no-array"
Instructions
Write a function SortListInsert
that inserts data_ref
in the linked list l
while keeping the list sorted in ascending order.
- During the tests the list passed as an argument will be already sorted.
Expected function and structure
func SortListInsert(l *NodeI, data_ref int) *NodeI{
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func PrintList(l *student.NodeI) {
it := l
for it != nil {
fmt.Print(it.Data, " -> ")
it = it.Next
}
fmt.Print(nil, "\n")
}
func listPushBack(l *student.NodeI, data int) *student.NodeI {
n := &student.NodeI{Data: data}
if l == nil {
return n
}
iterator := l
for iterator.Next != nil {
iterator = iterator.Next
}
iterator.Next = n
return l
}
func main() {
var link *student.NodeI
link = listPushBack(link, 1)
link = listPushBack(link, 4)
link = listPushBack(link, 9)
PrintList(link)
link = student.SortListInsert(link, -2)
link = student.SortListInsert(link, 2)
PrintList(link)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
1 -> 4 -> 9 -> <nil>
-2 -> 1 -> 2 -> 4 -> 9 -> <nil>
student@ubuntu:~/[[ROOT]]/test$
sortedlistmerge
Allowed functions
"--no-array"
Instructions
Write a function SortedListMerge
that merges two lists n1
and n2
in ascending order.
- During the tests
n1
andn2
will already be initially sorted.
Expected function and structure
func SortedListMerge(n1 *NodeI, n2 *NodeI) *NodeI {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func PrintList(l *student.NodeI) {
it := l
for it != nil {
fmt.Print(it.Data, " -> ")
it = it.Next
}
fmt.Print(nil, "\n")
}
func listPushBack(l *student.NodeI, data int) *student.NodeI {
n := &student.NodeI{Data: data}
if l == nil {
return n
}
iterator := l
for iterator.Next != nil {
iterator = iterator.Next
}
iterator.Next = n
return l
}
func main() {
var link *student.NodeI
var link2 *student.NodeI
link = listPushBack(link, 3)
link = listPushBack(link, 5)
link = listPushBack(link, 7)
link2 = listPushBack(link2, -2)
link2 = listPushBack(link2, 9)
PrintList(student.SortedListMerge(link2, link))
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
-2 -> 3 -> 5 -> 7 -> 9 -> <nil>
student@ubuntu:~/[[ROOT]]/test$
listremoveif
Allowed functions
"--no-array"
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
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 :
package main
import (
"fmt"
student ".."
)
func PrintList(l *student.List) {
it := l.Head
for it != nil {
fmt.Print(it.Data, " -> ")
it = it.Next
}
fmt.Print(nil, "\n")
}
func main() {
link := &student.List{}
link2 := &student.List{}
fmt.Println("----normal state----")
student.ListPushBack(link2, 1)
PrintList(link2)
student.ListRemoveIf(link2, 1)
fmt.Println("------answer-----")
PrintList(link2)
fmt.Println()
fmt.Println("----normal state----")
student.ListPushBack(link, 1)
student.ListPushBack(link, "Hello")
student.ListPushBack(link, 1)
student.ListPushBack(link, "There")
student.ListPushBack(link, 1)
student.ListPushBack(link, 1)
student.ListPushBack(link, "How")
student.ListPushBack(link, 1)
student.ListPushBack(link, "are")
student.ListPushBack(link, "you")
student.ListPushBack(link, 1)
PrintList(link)
student.ListRemoveIf(link, 1)
fmt.Println("------answer-----")
PrintList(link)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
----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>
student@ubuntu:~/[[ROOT]]/test$
btreetransplant
Instructions
In order to move subtrees around within the binary search tree, write a function, BTreeTransplant
, which replaces the subtree started by node
with the node rplc
in the tree given by root
.
Expected function
func BTreeTransplant(root, node, rplc *TreeNode) *TreeNode {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
root := &student.TreeNode{Data: "4"}
student.BTreeInsertData(root, "1")
student.BTreeInsertData(root, "7")
student.BTreeInsertData(root, "5")
node := student.BTreeSearchItem(root, "1")
replacement := &student.TreeNode{Data: "3"}
root = student.BTreeTransplant(root, node, replacement)
student.BTreeApplyInorder(root, fmt.Println)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
3
4
5
7
student@ubuntu:~/[[ROOT]]/test$
btreeapplybylevel
Instructions
Write a function, BTreeApplyByLevel
, that applies the function given by fn
to each node of the tree given by root
.
Expected function
func BTreeApplyByLevel(root *TreeNode, f func(...interface{}) (int, error)) {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
root := &student.TreeNode{Data: "4"}
student.BTreeInsertData(root, "1")
student.BTreeInsertData(root, "7")
student.BTreeInsertData(root, "5")
student.BTreeApplyByLevel(root, fmt.Println)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
4
1
7
5
student@ubuntu:~/[[ROOT]]/test$
btreedeletenode
Instructions
Write a function, BTreeDeleteNode
, that deletes node
from the tree given by root
.
The resulting tree should still follow the binary search tree rules.
Expected function
func BTreeDeleteNode(root, node *TreeNode) *TreeNode {
}
Usage
Here is a possible program to test your function :
package main
import (
"fmt"
student ".."
)
func main() {
root := &student.TreeNode{Data: "4"}
student.BTreeInsertData(root, "1")
student.BTreeInsertData(root, "7")
student.BTreeInsertData(root, "5")
node := student.BTreeSearchItem(root, "4")
fmt.Println("Before delete:")
student.BTreeApplyInorder(root, fmt.Println)
root = student.BTreeDeleteNode(root, node)
fmt.Println("After delete:")
student.BTreeApplyInorder(root, fmt.Println)
}
And its output :
student@ubuntu:~/[[ROOT]]/test$ go build
student@ubuntu:~/[[ROOT]]/test$ ./test
Before delete:
1
4
5
7
After delete:
1
5
7
student@ubuntu:~/[[ROOT]]/test$