Sqrt(x)

Implement int sqrt(int x).

Compute and return the square root of x.

class Solution {
public:
    int sqrt(int x)
    {
        if (x <= 0) return 0;
        long long minv = 1;
        long long maxv = x/2 + 1;
        long long mid = 0;
        while(minv <= maxv)
        {
            mid = (minv + maxv) / 2;
            long long val = mid*mid;
            if (val == x)
                return mid;
            else if (val < x)
                minv = mid + 1;
            else
                maxv = mid - 1;
        }
        return maxv;
    }
};