Cod sursa(job #2227557)

Utilizator AndreiTurcasTurcas Andrei AndreiTurcas Data 1 august 2018 02:14:27
Problema Distante Scor 60
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.38 kb
#include <iostream>
#include <fstream>
#include <queue>
#include <vector>
#include <cstring>
#define oo 0x3f3f3f3f
using namespace std;

ifstream f("distante.in");
ofstream g("distante.out");

int T, n, m, s;
vector<pair<int,int> > G[50001];
queue<int> Q;
vector<int> Dist(50001);
vector<bool> B(50001);

bool BelFord()
{
    int nr = 1;
    B[s] = 1;
    Q.push(s);
    while(!Q.empty())
    {
        int v = Q.front();
        for(vector<pair<int,int> > :: iterator it = G[v].begin(); it != G[v].end(); ++it)
        {
            int v2 = it->first, d = it->second;
            if(Dist[v] + d < Dist[v2]) return false;
            if(Dist[v] + d > Dist[v2] && !B[v2]) Q.push(v2);
            if(Dist[v] + d == Dist[v2] && !B[v2]) {nr++; B[v2] = 1; Q.push(v2);}
        }
        Q.pop();
    }
    if(nr == n) return true;
    return false;
}

int main()
{
    f >> T;
    for(int i = 1; i <= T; ++i)
    {
        f >> n >> m >> s;
        for(int j = 1; j <= n; ++j)
            f >> Dist[j];
        for(int j = 1; j <= m; ++j)
        {
            int x, y, c;
            f >> x >> y >> c;
            G[x].push_back(make_pair(y, c));
            G[y].push_back(make_pair(x, c));
        }
        if(BelFord()) g << "DA\n";
        else g << "NU\n";
        fill(B.begin(), B.end(), 0);
        for(int k = 1; k <= n; ++k) G[k].clear();
    }
}