How do I convert a char to an int in C and C++?

In C language, there are three methods to convert a char type variable to an int. These are given as follows −

• sscanf()
• atoi()
• Typecasting

Here is an example of converting char to int in C language,

Example

#include<stdio.h>
#include<stdlib.h>
int main() {
   const char *str = "12345";
   char c = 's';
   int x, y, z;

   sscanf(str, "%d", &x); // Using sscanf
   printf("\nThe value of x : %d", x);

   y = atoi(str); // Using atoi()
   printf("\nThe value of y : %d", y);

   z = (int)(c); // Using typecasting
   printf("\nThe value of z : %d", z);

   return 0;
}

Output

Here is the output:

The value of x : 12345
The value of y : 12345
The value of z : 115

In C++ language, there are two following methods to convert a char type variable into an int −

• stoi()
• Typecasting

Here is an example of converting char to int in C++ language,

Example

#include <iostream>
#include <string>
using namespace std;
int main() {
   char s1[] = "45";
   char c = 's';

   int x = stoi(s1);
   cout << "The value of x : " << x;

   int y = (int)(c);
   cout << "\nThe value of y : " << y;

   return 0;
}

Output

Here is the output

The value of x : 45
The value of y : 115