Binary number Adding in C

 #include<stdio.h>

int binaryadd(int a, int b)

{

 

    long binary1, binary2;

    int i = 0, remainder = 0, sum[20];

 

    printf("Enter the first binary number: ");

    scanf("%d", &binary1);

    printf("Enter the second binary number: ");

    scanf("%d", &binary2);

    while (binary1 != 0 || binary2 != 0)

    {

        sum[i++] =(binary1 % 10 + binary2 % 10 + remainder) % 2;

        remainder =(binary1 % 10 + binary2 % 10 + remainder) / 2;

        binary1 = binary1 / 10;

        binary2 = binary2 / 10;

    }

    if (remainder != 0)

        sum[i++] = remainder;

    --i;

    printf("Sum of two binary numbers: ");

    while (i >= 0)

        printf("%d", sum[i--]);

    return 0;

}

int main()

{

    long binary1,binary2;

    binaryadd(binary1,binary2);

   

   

    return 0;

}