Submission #473722

#	Time	Username	Problem	Language	Result	Execution time	Memory
473722		ntabc05101	Mag (COCI16_mag)	C++14	12 / 120	445 ms	152300 KiB

mag

#include<bits/stdc++.h>
using namespace std;

const int mxN = 1000000;

bool choose[mxN];
vector<int> adj[mxN];
int ans = 0;
int d[mxN + 1];

void dfs(int u, int p = -1) {
  vector<int> v;
  int mx = -1, mx2 = -1;
  for (auto &to: adj[u]) {
    if (to != p) {
      dfs(to, u);
      if (choose[to]) {
        mx2 = max(mx2, d[to]);
        if (mx2 > mx) {
          swap(mx2, mx);
        }
      }
    }
  }

  if (choose[u]) {
    d[u] = 1;
    if (~mx) {
      ans = max(ans, mx + 1);
      d[u] = mx + 1;
    }
    if (~mx2) {
      ans = max(ans, mx + mx2);
    }
  }
}

int main() {
  cin.tie(0)->sync_with_stdio(0);

  int n; cin >> n;
  for (int i = 0, x, y; i < n - 1; i++) {
    cin >> x >> y; x--; y--;

    adj[x].push_back(y);
    adj[y].push_back(x);
  }

  int mn = 1e9;
  for (int i = 0, x; i < n; i++) {
    cin >> x;
    choose[i] = x == 1;
    mn = min(mn, x);
  }

  if (mn > 1) {
    cout << mn << "/1";
  }
  else {
    ans = 1;
    dfs(0);
    cout << "1/" << ans;
  }

  cout << endl;

  return 0;
}

• Subtask 1: 12 / 12
• Subtask 2: 0 / 12
• Subtask 3: 0 / 12
• Subtask 4: 0 / 12
• Subtask 5: 0 / 12
• Subtask 6: 0 / 12
• Subtask 7: 0 / 12
• Subtask 8: 0 / 12
• Subtask 9: 0 / 12
• Subtask 10: 0 / 12