Cod sursa(job #2374214)

Utilizator mariastStoichitescu Maria mariast Data 7 martie 2019 17:30:57
Problema Algoritmul Bellman-Ford Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.1 kb
#include<fstream>
#include<vector>
#include<queue>
using namespace std;
ifstream f ("bellmanford.in");
ofstream g ("bellmanford.out");
vector <int>G[50010],cost[50010];
queue<int> q;
int viz[50010],ciclu[50010],T[50010],n,m,x,y,ct,OK;
void bfs(int x){
    T[x]=0;
    viz[x]=1;
    q.push(x);
    while(!q.empty()){
        x=q.front();
        ++ciclu[x];
        if(ciclu[x]>n){
            OK=0;
            g<<"Ciclu negativ!";
            return;
        }
        for(int i=0;i<G[x].size();++i){
            if(T[x]+cost[x][i]<T[G[x][i]]){
                T[G[x][i]]=T[x]+cost[x][i];
                if(!viz[G[x][i]]){
                    q.push(G[x][i]);
                    viz[G[x][i]]=1;
                }
            }
        }
        viz[x]=0;
        q.pop();
    }
}

int main()
{
    f>>n>>m;
    for(int i=1;i<=n;++i){
        f>>x>>y>>ct;
        G[x].push_back(y);
        cost[x].push_back(ct);
    }
    for(int i=2;i<=n;++i)T[i]=999999999;
    bfs(1);
    OK=1;
    if(OK){
        for(int i=2;i<=n;++i)
            g<<T[i]<<" ";
    }
    return 0;
}