LeetCode: Valid Palindrome

基本一次过吧，题目没说数字要算进去啊。。

 1 class Solution {

 2 public:

 3     bool check(string t) {

 4         for (int i = 0; i < t.size(); i++) {

 5             if (t[i] != t[t.size()-1-i]) return false;

 6         }

 7         return true;

 8     }

 9     bool isPalindrome(string s) {

10         // Start typing your C/C++ solution below

11         // DO NOT write int main() function

12         string t;

13         for (int i = 0; i < s.size(); i++) {

14             if (s[i] >= 'A' && s[i] <= 'Z') t += (s[i] + 'a' - 'A');

15             if (s[i] >= 'a' && s[i] <= 'z') t += s[i];

16             if (s[i] >= '0' && s[i] <= '9') t += s[i];

17         }

18         return check(t);

19     }

20 };