Submission #1180820

#	Time	Username	Problem	Language	Result	Execution time	Memory
1180820		julia_08	Graph (BOI20_graph)	C++20	0 / 100	1 ms	2632 KiB

Graph

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

const int MAXN = 1e5 + 10;

int marc[MAXN], a[MAXN], b[MAXN];

double val[MAXN];

vector<pair<int, int>> adj[MAXN];

vector<int> comp;

double x; bool ok;

void dfs(int v){

  marc[v] = 1;
  comp.push_back(v);

  for(auto [u, w] : adj[v]){
    if(!marc[u]){
      a[u] = -a[v], b[u] = w - b[v];
      dfs(u);

    } else{
      if(a[u] + a[v] != 0){
        x = ((double) (w - b[u] - b[v])) / ((double) (a[u] + a[v]));
        ok = false;
      }

    }
  }

}

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

  int n, m; cin >> n >> m;

  for(int i=1; i<=m; i++){
    int a, b, c; cin >> a >> b >> c;
    adj[a].push_back({b, c});
    adj[b].push_back({a, c});
  }

  for(int i=1; i<=n; i++){
    if(!marc[i]){

      comp.clear(); ok = true;

      a[i] = 1, b[i] = 0;

      dfs(i);

      if(ok){

        vector<int> median;

        for(auto j : comp){
          if(a[j] > 0) median.push_back(b[j]);
          if(a[j] < 0) median.push_back(-b[j]);
        }

        sort(median.begin(), median.end());

        x = (double) median[(int) median.size() / 2];

      }

      for(auto j : comp) val[j] = a[j] * x + b[j];

    }
  }

  for(int i=1; i<=n; i++){
    for(auto [j, w] : adj[i]){
      if(val[i] + val[j] - w > 1e-6){
        cout << "NO\n";
        return 0;
      }
    }
  }

  cout << "YES\n";

  cout << fixed << setprecision(6);

  for(int i=1; i<=n; i++) cout << val[i] << " ";

  cout << "\n";

  return 0;
}

• Subtask 1: 0 / 12
• Subtask 2: 0 / 17
• Subtask 3: 0 / 24
• Subtask 4: 0 / 42
• Subtask 5: 0 / 5