foldint subject

subjects/foldint.en.md

@@ -0,0 +1,64 @@
+## foldint
+
+## **WARNING! VERY IMPORTANT!**
+
+For this exercise a function will be tested **with the exam own main**. However the student **still needs** to submit a structured program:
+
+This means that:
+
+- The package needs to be named `package main`.
+- The submitted code needs one declared function main(```func main()```) even if empty.
+- The function main declared needs to **also pass** the `Restrictions Checker\`(illegal functions tester). It is advised for the student to just empty the function main after its own testings are done.
+- Every other rules are obviously the same than for a `program`.
+
+### Instructions
+
+Write a function called `FoldInt` that simulates the behavior of reduce from JavaScript.
+
+The function should have as parameters a function, `f func(int, int) int` a slice of integers, `slice []int` and an int `acc int`. You should apply for each element of the slice the arithmetic function, saving and printing it. The function will be tested with our own functions `Add, Sub, and Mul`.
+
+### Expected function
+
+```go
+func FoldInt(f func(int, int) int, slice []int, acc int) {
+
+}
+```
+
+### Usage
+
+Here is a possible program to test your function:
+
+```go
+package main
+
+func main() {
+  table := []int{1, 2, 3}
+  ac := 93
+  FoldInt(Add, table, ac)
+  FoldInt(Mul, table, ac)
+  FoldInt(Sub, table, ac)
+  fmt.Println()
+  
+  table = []int{0}
+	FoldInt(Add, table, ac)
+	FoldInt(Mul, table, ac)
+	FoldInt(Sub, table, ac)
+}
+
+```
+
+And its output :
+
+```console
+student@ubuntu:~/[[ROOT]]/test$ go build
+student@ubuntu:~/[[ROOT]]/test$ ./test
+99
+558
+87
+
+93
+0
+93
+student@ubuntu:~/[[ROOT]]/test$
+```