Without modulus operator: (works with any range of values)

Code:
int ttobit(int num)
{
    int power = log2(num);
    int res[99];
    int sum = 0;
    int counter = 0;

    while(power >= 0)
    {
        sum = sum + pow(2,power);

        if(num>=sum) {res[counter] = 1;}
        else
        {
            sum = sum - pow(2,power);
...