public/subjects/atoi-exam

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

func Atoi(s string) int {

}

Usage

Here is a possible program to test your function :

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 :

$ go run .
12345
12345
0
0
1234
-1234
0
0
$

Notions

• strconv/Atoi