Lennot

#include<iostream>
#include<vector>
#include<map>
#include<set>
#include<algorithm>
#include<cmath>
#include<utility>
#include<queue>

using namespace std;

int main(void) {
  int64_t n,m;
  cin >> n >> m;
  vector<vector<pair<int64_t,int64_t>>> edges(2*n);
  for(int64_t i=0;i<m;i++) {
    int64_t a,b,c;
    cin >> a >> b >> c;
    a--;
    b--;
    edges[a].push_back(make_pair(b+n,-c));
    edges[a+n].push_back(make_pair(b,0));
  }

  priority_queue<pair<int64_t,int64_t>> q;
  vector<bool> visited(2*n,false);
  q.push(make_pair(0,0));
  int64_t best=-1000000000000000000;
  while(!q.empty()) {
    pair<int64_t,int64_t> cur=q.top();
    q.pop();
    if(visited[cur.second]) continue;
    visited[cur.second]=true;
    if(cur.second == n-1 || cur.second == 2*n-1) {
      best=max(best,cur.first);
    }
    for(auto e: edges[cur.second]) {
      if(!visited[e.first]) {
        q.push(make_pair(cur.first+e.second, e.first));
      }
    }
  }
  cout << -best << endl;
  return 0;
}

Test 1

Group: 1

Verdict: ACCEPTED

Test 2

Group: 1

Verdict: ACCEPTED

Test 3

Group: 1

Verdict: ACCEPTED

Test 4

Group: 1

Verdict: ACCEPTED

Test 5

Group: 1

Verdict: ACCEPTED

Test 6

Group: 2

Verdict: ACCEPTED

Test 7

Group: 2

Verdict: ACCEPTED

Test 8

Group: 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: ACCEPTED

Test 10

Group: 2

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED

Test 16

Group: 3

Verdict: ACCEPTED

Test 17

Group: 3

Verdict: ACCEPTED