leetcode633

用开方的思想来解题。

bool judgeSquareSum(int c) {
    int h = pow(c, 0.5);
    for (int i = ; i <= h; i++)
    {
        double left = pow(c - pow(i, ), 0.5);
        if (left - int(left) == 0.0)
        {
            return true;
        }
    }
    return false;
}

补充一个phthon的实现，使用双指针思想：

 class Solution:
     def judgeSquareSum(self, c: int) -> bool:
         i=0
         j=int(c ** 0.5)
         while i<=j:
             target = i*i +j*j
             if target==c:
                 return True
             elif target>c:
                 j-=1
             else:
                 i+=1

         return False