69.x 的平方根

😂二分查找

class Solution {
public:
    int mySqrt(int x) {
        int lo = 1,
        hi = x,
        mi;
        while(lo < hi) {
            mi = lo + (hi - lo) / 2;
            if(mi < x / mi) {
                lo = mi + 1;
            } else {
                hi = mi;
            }
        }
        if(lo > x / lo)
            return lo - 1;
        return lo;
    }
};

Accepted

1017/1017 cases passed (4 ms)

Your runtime beats 83.41 % of cpp submissions

Your memory usage beats 48.78 % of cpp submissions (8.2 MB)