Submission #1088378

#	Time	Username	Problem	Language	Result	Execution time	Memory
1088378		Rolo678	Aesthetic (NOI20_aesthetic)	C++14	0 / 100	17 ms	24412 KiB

Aesthetic

#include <bits/stdc++.h>
using namespace std;
#define int long long
vector<vector<pair<int,int>>>g(3e5+5);
vector<long long>dp2(3e5+5,-1);
 vector<long long>dp(3e5+5,-1);

signed main()
{
    freopen("5-2.in", "r", stdin);

  int n,m;
  cin >> n>>m;
 // cin >> n >> m;
  vector<pair<int,int>>e(m+1);
  for(int i = 1;i<=m;i++)
  {
    int a,b,w;
    cin >> a >> b >> w;
    //cout << 'o';
    g[a].push_back({b,i});
    g[b].push_back({a,i});
    e[i] = {a,b};
//cout << 'o';
  }

  //dfs();
  dp[1] =0;
  queue<int>q;
  q.push(1);
  while(!q.empty())
  {
   int v = q.front();
    q.pop();
    for(auto u : g[v])
    {
      if(dp[u.first] == -1)
      {
        q.push(u.first);
        dp[u.first] = dp[v] + 1;
      }
    }
  }
    dp2[n] =0;
  //queue<int>q;
  q.push(n);
  while(!q.empty())
  {
    int v = q.front();
    q.pop();
    for(auto u : g[v])
    {
      if(dp2[u.first] == -1)
      {
        q.push(u.first);
        dp2[u.first] = dp2[v] + 1;
      }
    }
  }
  int mn = 1e9+5;
  int num = 0;
  int mn2 = 1e9+5;
  int s =0;
  for(int i = 1;i<=m;i++)
  {
    int v = e[i].first;
    int u = e[i].second;
    if(dp[u] == mn && dp2[v]== mn2)
    {
      num++;
    }
    else if(dp[u] + dp2[v]+1 <mn+mn2+1)
    {
       mn = dp[u];
       mn2 =  dp2[v];
     num = 1;
    }
     if(i==m && (dp[u] + dp2[v]+1 <mn+mn2+1))
    {
      num++;
       s= 1;
    }
   // cout <<  dp[i.first] + dp2[i.second]+1 << '\n';
  }
   cout << mn+mn2+1 + ((num == 1)&& !s);
}

Compilation message (stderr)

Aesthetic.cpp: In function 'int main()':
Aesthetic.cpp:10:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   10 |     freopen("5-2.in", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 8
• Subtask 3: 0 / 7
• Subtask 4: 0 / 15
• Subtask 5: 0 / 16
• Subtask 6: 0 / 22
• Subtask 7: 0 / 27