func_code_string: #include <bits/stdc++.h>   using namespace std;   void func() {     string s;     cin >> s;     long long n = s.length();     long long i = 1, len = 0, pre[n];     pre[0] = 0;     while (i < n) {       if (s[i] == s[len]) {         len++;         pre[i++] = len;       } else {         if (len == 0) {           pre[i++] = 0;         } else {           len = pre[len - 1];         }       }     }     if (pre[n - 1] == 0) {       cout <<  Just a legend             <<   n ;       return;     }     for (long long i = 0; i < n - 1; ++i) {       if (pre[i] == pre[n - 1]) {         cout << s.substr(0, pre[n - 1]) <<   n ;         return;       }     }     if (pre[pre[n - 1] - 1] == 0) {       cout <<  Just a legend             <<   n ;       return;     }     cout << s.substr(0, pre[pre[n - 1] - 1]) <<   n ;   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     long long t = 1;     while (t--) {       func();     }   }   