Submission #198366

#	Time	Username	Problem	Language	Result	Execution time	Memory
198366		alrad	Lampice (COCI19_lampice)	C++17	17 / 110	1172 ms	3816 KiB

lampice

#include <bits/stdc++.h>

using namespace std;

const int N = 5e4 + 2;

vector<vector<int> > g(N , vector<int>());
int ans = 0;
string all;
string walk = "";

bool good(string cur) {
   string other = cur;
   reverse(other.begin() , other.end());
   return other == cur;
}

void dfs(int v , int p = -1) {
   walk.push_back(all[v - 1]);
   if (good(walk)) {
      ans = max(ans , (int)walk.size());
   }
   for (int to : g[v]) {
      if (to != p) {
         dfs(to , v);
         walk.pop_back();
      }
   }
}

int main() {
   ios_base :: sync_with_stdio(0);
   cin.tie(0) , cout.tie(0);
   int n;
   cin >> n;
   cin >> all;
   for (int i = 1; i < n; i++) {
      int u , v;
      cin >> u >> v;
      g[u].push_back(v);
      g[v].push_back(u);
   }
   if (n <= 3000) {
      //solve subtask 1
      for (int i = 1; i <= n; i++) {
         walk = "";
         dfs(i);
      }
      cout << ans << '\n';
      return 0;
   }
   return 0;
}

• Subtask 1: 17 / 17
• Subtask 2: 0 / 25
• Subtask 3: 0 / 31
• Subtask 4: 0 / 37