Cod sursa(job #778193)

Utilizator visanrVisan Radu visanr Data 14 august 2012 11:36:08
Problema Distante Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 2.22 kb
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <queue>
#include <vector>
#include <algorithm>
using namespace std;

#define nmax 50010
#define pb push_back
#define mp make_pair
#define to first
#define cost second


vector<pair<int, int> > G[nmax];
int N, M, T, A, B, C, S;
int c[nmax], BFcost[nmax];
bool InQueue[nmax];

void BellmanFord(int startNode);


int main()
{
    freopen("distante.in", "r", stdin);
    freopen("distante.out", "w", stdout);
    int i;
    scanf("%i", &T);
    for(; T; T --)
    {
          scanf("%i %i %i", &N, &M, &S);
          for(i = 1; i <= N; i++) scanf("%i", &c[i]);
          for(i = 1; i <= M; i++)
          {
                scanf("%i %i %i", &A, &B, &C);
                G[A].pb(mp(B, C));
                G[B].pb(mp(A, C));
          }
          BellmanFord(S);
          bool ok = false;
          for(i = 1; i <= N && !ok; i++)
                if(BFcost[i] != c[i])
                             ok = true;
          if(ok) printf("NU\n");
          else printf("DA\n");
    }
    scanf("%i", &i);
    return 0;
}

void BellmanFord(int startNode)
{
     int i;
     for(i = 1; i <= N; i++) BFcost[i] = 0x3f3f3f3f, InQueue[i] = false;
     BFcost[startNode] = 0;
     queue<int> Q;
     Q.push(startNode);
     InQueue[startNode] = true;
     vector<pair<int, int> > :: iterator it;
     while(!Q.empty())
     {
                      int node = Q.front();
                      Q.pop();
                      InQueue[node] = false;
                      for(it = G[node].begin(); it != G[node].end(); ++ it)
                      {
                             if(BFcost[it -> to] > BFcost[node] + it -> cost)
                             {
                                          BFcost[it -> to] = BFcost[node] + it -> cost;
                                          if(!InQueue[it -> to])
                                          {
                                                         InQueue[it -> to] = true;
                                                         Q.push(it -> to);
                                          }
                             }
                      }
     }
}