Converting the String to an Integer in C
In this tutorial, we are going to learn about how to convert the string to a integer in C language.
Using atoi() function
In C, we can use the atoi()
function to convert a numeric string to a integer.
The
atoi()
function is available instdlib.h
library.
Here is an example, that converts the string "1011"
to an integer 1011
:
#include<stdio.h>
#include <stdlib.h>
int main() {
// Converting a numeric string to integer
char str[5] = "1011";
int a = atoi(str);
printf("Converting '1011': %d\n", a);
}
If a string starts with alpanumeric then atoi()
function returns 0
.
Example:
#include<stdio.h>
#include <stdlib.h>
int main() {
// Converting a numeric string to integer
char str[5] = "olaa";
int a = atoi(str);
printf("Converting '1011': %d\n", a);
}
Output:
0