Q-69 Sqrt(x).java

//Find the the rounding down sqrt of x without using any api function
public int mySqrt(int x) {
        if (x == 0) return 0;
        int start = 1, end = x;
        while (start < end) {
            int mid = start + (end - start) / 2;
            if (mid <= x / mid && mid + 1 > x / (mid + 1))
                return mid;
            else if (mid > x / mid)
                end = mid;
            else start = mid + 1;
        }
        return start;
    }