Submission #600752

#	Time	Username	Problem	Language	Result	Execution time	Memory
600752		narvalo	Ferries (NOI13_ferries)	C++17	7 / 40	139 ms	32632 KiB

ferries

#include <bits/stdc++.h>

using namespace std;

int ferries(int n , int m , vector<int> a , vector<int> b , vector<int> c) {
  vector<vector<pair<int , int>>> adj(n);
  for (int i = 0 ; i < m ; i++) {
    a[i] -= 1 , b[i] -= 1;
    adj[a[i]].emplace_back(b[i] , c[i]);
  }
  vector<int> s , d;
  for (int i = 0 ; i < (int)adj[0].size() ; i += 1) {
    s.push_back(adj[0][i].second);
  }
  sort(s.begin() , s.end());
  for (int i = 1 ; i < n - 1 ; i += 1) {
    d.push_back(adj[i][0].second);
  }
  sort(d.begin() , d.end());
  assert((int)s.size() == (int)d.size());
  auto Get = [&]() {
    int val = (int)1e9;
    for (int i = 0 ; i < (int)s.size() ; i += 1) {
      val = min(val , s[i] + d[(int)s.size() - 1 - i]);
    }
    return val;
  };
  int res = Get();
  reverse(s.begin() , s.end());
  reverse(d.begin() , d.end());
  res = max(res , Get());
  return res;
}

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n , m;
  cin >> n >> m;
  vector<int> a(m) , b(m) , c(m);
  for (int i = 0 ; i < m ; i += 1) {
    cin >> a[i] >> b[i] >> c[i];
  }
  cout << ferries(n , m , a , b , c) << '\n';
}

• Subtask 1: 7 / 7
• Subtask 2: 0 / 10
• Subtask 3: 0 / 11
• Subtask 4: 0 / 12