Cod sursa(job #2603195)

Utilizator avtobusAvtobus avtobus Data 18 aprilie 2020 18:34:10
Problema Algoritmul lui Dijkstra Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.15 kb
#include <stdio.h>
#include <bits/stdc++.h>

#define rep(i, n) for(int i = 0; i < n; i++)

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
const int INF = 0x3f3f3f3f;

ifstream fin ("dijkstra.in");
ofstream fout ("dijkstra.out");

const int Nmax = 50444;
int N, M, d[Nmax];
char vis[Nmax];
vector<pii> G[Nmax];

int main(void) {
  // freopen("dijkstra.in", "r", stdin);
  std::ios_base::sync_with_stdio(false);
  std::cin.tie(NULL);

  fin >> N >> M;
  memset(d, 0x3f, N*sizeof(int));

  int a, b, c;
  rep(i, M) {
    fin >> a >> b >> c;
    --a;
    --b;
    G[a].push_back({b, c});
  }

  priority_queue<pii, vector<pii>, greater<pii> > Q;
  Q.push({0, 0}); d[0] = 0;
  while(!Q.empty()) {
    auto X = Q.top(); Q.pop();
    if (vis[X.second]) { continue; }

    int dist = X.first, nod = X.second;
    d[nod] = dist;
    vis[nod] = 1;

    for(auto Y: G[nod]) {
      int nbr = Y.first, cost = Y.second;
      if (d[nbr] > dist + cost) {
        Q.push({dist+cost, nbr});
        d[nbr] = dist + cost;
      }
    }
  }
  for(int i = 1; i < N; i++) { fout << (d[i] == INF ? 0 : d[i]) << ' '; }
  fout << endl;

  return 0;
}