Submission #337279

#	Time	Username	Problem	Language	Result	Execution time	Memory
337279		boykut	Shymbulak (IZhO14_shymbulak)	C++14	50 / 100	605 ms	876 KiB

shymbulak

#include <bits/stdc++.h>

using namespace std;

const int MAXN = 5005;
const int INF = 2'000'000'000;

int n;
vector<int> g[MAXN];

int cur = 0, cnt = 0;

void bfs(int a) {
   int dist[MAXN];
   fill (dist, dist + MAXN, INF);
   
   queue < int > q;
   q.push(a);
   dist[a] = 0;
   
   while (!q.empty()) {
      int v = q.front();
      q.pop();
      for (auto i : g[v]) {
         if (dist[i] >= dist[v] + 1) {
            q.push(i);
            dist[i] = dist[v] + 1;
            if (dist[i] == cur) {
               cnt++;
            } else if (dist[i] > cur) {
               cur = dist[i];
               cnt = 1;
            }
         }
      }
   }
   return;
}

signed main() {
   ios::sync_with_stdio(0);
   cin.tie(0);
   
   cin >> n;
   for (int i = 0; i < n; i++) {
      int a, b;
      cin >> a >> b;
      g[a].push_back(b);
      g[b].push_back(a);
   }
   
   int ansD = 0, cntWay = 0;
   for (int i = 1; i <= n; i++) {
      cur = 0;
      cnt = 0;
      bfs(i);
      if (cur == ansD) {
         cntWay += cnt;
      } else if (cur > ansD) {
         ansD = cur;
         cntWay = cnt;
      }
   }
   
   cout << cntWay / 2 << endl;
   return 0;
}

• Subtask 1: 30 / 30
• Subtask 2: 20 / 20
• Subtask 3: 0 / 50