题解 | #密码截取#

#include <iostream>
#include <algorithm>
using namespace std;

int Palindromic(string& ss, int i, int j){
    for(int n = ss.size();i >= 0 && j < n && ss[i] == ss[j];i--,j++){}
    return j - i - 1;
}

int main() {
    string ss;
    while (cin >> ss) {
        int maxLen = 0;
        int n = ss.size();
        for(int i = 1; i < n; i++){
            int len1 = Palindromic(ss, i, i);
            int len2 = Palindromic(ss, i, i - 1);
            maxLen = max({maxLen, len1, len2});
        }
        cout << maxLen << endl;
    }
}
// 64 位输出请用 printf("%lld")