Cod sursa(job #763636)

Utilizator test666013Testez test666013 Data 2 iulie 2012 19:14:58
Problema Algoritmul Bellman-Ford Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.15 kb
#include <cstdio>
#include <vector>
#include <set>
#include <algorithm>
using namespace std;
#define MAX 50005
#define INF 0xffffff

vector<pair<int,int> >g[MAX];
set<int>s,v;

int n,d[MAX];

void bellman_ford(){
    bool ok = 0;
    for(int i=2;i<=n;i++)d[i] = INF;
    s.insert(1);
int x,y,c;
    for(int k=1;k<=n;k++)
    {
        ok = 0;
        while(s.size() > 0)
        {
            x = *s.begin();
            s.erase(s.begin());
            for(int i=0;i<g[x].size();i++)
            {
                y = g[x][i].second;
                c = g[x][i].first;
                if(d[y] > d[x] + c)
                {
                    ok = 1;
                    d[y] = d[x] + c;
                    v.insert(y);
                }
            }
        }
        swap(s,v);
    }
    if(ok)printf("Ciclu negativ!\n"); else
    for(int i=2;i<=n;i++)printf("%d ",d[i]);
}

int main(){
    int m,x,y,c;
    freopen("bellmanford.in","r",stdin);
    freopen("bellmanford.out","w",stdout);
        scanf("%d %d",&n,&m);
        while(m--)
        {
            scanf("%d %d %d",&x,&y,&c);
            g[x].push_back(make_pair(c,y));
        }
    bellman_ford();
    return 0;
}