题目
Given a non-negative integer c, decide whether there’re two integers a and b such that a^2 + b^2 = c
解题思路
使用左右两个指针0和sqrt(c)，求两个数的平方和，如果小于c，left+1，大于c，right+1
代码
class Solution:
def judgeSquareSum(self, c: int) -> bool:
left, right = 0, int(c**0.5)
while left <= right:
cur = left * left + right * right
if cur < c:
left += 1
elif cur > c:
right -= 1
else:
return True
return False
