binary to octal

#include <stdio.h>

int main()
{
    long long int binary, octal = 0, i = 1, rem;

    printf("Enter any binary number: ");
    scanf("%lld", &binary);
    while (binary != 0)
    {
        rem = binary % 10;
        octal = octal + rem * i;
        i = i * 2;
        binary = binary / 10;
    }
    printf("Octal number = %llo\n", octal);
    return 0;
}