c program for binary to decimal code example

Example 1: binary to hexadecimal in c

/*
 * C Program to Convert Binary to Hexadecimal 
 * My Github: https://github.com/krishnan-tech
 */
#include <stdio.h>
 
int main()
{
    long int binaryval, hexadecimalval = 0, i = 1, remainder;
 
    printf("Enter the binary number: ");
    scanf("%ld", &binaryval);
    while (binaryval != 0)
    {
        remainder = binaryval % 10;
        hexadecimalval = hexadecimalval + remainder * i;
        i = i * 2;
        binaryval = binaryval / 10;
    }
    printf("Equivalent hexadecimal value: %lX", hexadecimalval);
    return 0;
}

Example 2: how to convert a binary number to decimal in C

#include <math.h>
#include <stdio.h>
int convert(long long n);
int main() {
    long long n;
    printf("Enter a binary number: ");
    scanf("%lld", &n);
    printf("%lld in binary = %d in decimal", n, convert(n));
    return 0;
}

int convert(long long n) {
    int dec = 0, i = 0, rem;
    while (n != 0) {
        rem = n % 10;
        n /= 10;
        dec += rem * pow(2, i);
        ++i;
    }
    return dec;
}