P3805

CODE

#include <iostream>
#include <string>
using namespace std;
int expandAroundCenter(const string& s, int left, int right) {
    while (left >= 0 && right < s.length() && s[left] == s[right]) {
        left--;
        right++;
    }
    return right - left - 1;
}
int longestPalindromeSubstring(const string& s) {
    if (s.empty()) return 0;
    int maxLength = 1;
    for (int i = 0; i < s.length(); ++i) {
        int len1 = expandAroundCenter(s, i, i); 
        int len2 = expandAroundCenter(s, i, i + 1);
        maxLength = max(maxLength, max(len1, len2));
    }
    return maxLength;
}
int main() {
    string s;
    cin >> s;
    cout << longestPalindromeSubstring(s) << endl;
    return 0;
}

码风有点丑，勿喷

测评结果