NC141 #判断回文#
判断回文
http://www.nowcoder.com/practice/e297fdd8e9f543059b0b5f05f3a7f3b2
双指针。别用递归，字符串太长了会爆栈。
class Solution {
public:
bool judge(string str) {
int len = str.size();
int left = 0, right = len - 1;
while(left <= right)
{
if(str[left] != str[right]) return false;
left++, right--;
}
return true;
}
};