LeetCode Sqrt(x)

Implement int sqrt(int x).

Compute and return the square root of x.

class Solution {
public:
    //二分查找
	int sqrt(int x) {
		long long left = 0, right = x;
		while (left <= right) {
			long long mid = (left + right) / 2;
			if (mid*mid == x)
				return mid;
			else if (mid*mid < x)
				left = mid + 1;
			else
				right = mid - 1;

		}
		return right;
	}
};