Program for convert binary to decimal

/*  Program for convert binary to decimal */

#include <stdio.h>

#include <math.h>

void main()

{

    long int n;

    int dec = 0, temp = 0, r;

    clrscr();

    printf("Enter a binary number: ");

    scanf("%ld", &n);

    while (n!=0)

    {

        r = n % 10;

        n = n / 10;

        dec = dec + r * pow(2,temp);

        temp++;

    }

    printf("\n\n Equivalent decimal number is: %d", dec);

   getch();

}