Leetcode刷题112-69. x的平方根(C++详细解法！！！)

Come from : [https://leetcode-cn.com/problems/sqrtx/]

)

1.Question

Implement int sqrt(int x).

Compute and return the square root of x, where x is guaranteed to be a non-negative integer.

Since the return type is an integer, the decimal digits are truncated and only the integer part of the result is returned.

Example 1 :

Input: 4
Output: 2

Example 2 :

Input: 8
Output: 2
Explanation: The square root of 8 is 2.82842..., and since 
             the decimal part is truncated, 2 is returned.

2.Answer

easy类型题目。。

我的方法1：（逗比解法）
AC代码如下：

class Solution {
   
   
public:
    int mySqrt(int x) {
   
   
      
        int res = 0;
        
        for(long i = 0; i <= 46340; ++i)  //哈哈哈
        {
   
   
            if( i*i == x || (i*i < x && (i