Cod sursa(job #1919668)

Utilizator victorpapa98Papa Victor-Alexandru victorpapa98 Data 9 martie 2017 20:29:47
Problema Algoritmul Bellman-Ford Scor 90
Compilator cpp Status done
Runda Arhiva educationala Marime 1.47 kb
# include <cstdio>
# include <vector>
# include <queue>
# include <algorithm>
using namespace std;

FILE *f = freopen("bellmanford.in", "r", stdin);
FILE *g = freopen("bellmanford.out", "w", stdout);

const int N_MAX = 50010;

vector < pair <int, int> >  G[N_MAX];
queue <int> q;
int d[N_MAX];
bool inQueue[N_MAX];


int vizitat[N_MAX];

int n, m;

void read(){
    scanf("%d %d", &n, &m);

    for (int i=1; i<=m; i++){
        int x, y, c;

        scanf("%d %d %d", &x, &y, &c);

        G[x].push_back(make_pair(y, c));
    }
}

void write(){
    for (int i=2; i<=n; i++){
        if (d[i] != 1e9)
            printf("%d ", d[i]);
        else
            printf("-1 ");
    }
}

void solve(){
    q.push(1);

    for (int i=2; i<=n; i++)
        d[i] = 1e9;

    d[1] = 0;

    while (!q.empty() && vizitat[q.front()] <= n){
        int nod = q.front();
        q.pop();
        inQueue[nod] = false;

        for (pair <int, int> vecin : G[nod]){
            if (d[vecin.first] > d[nod] + vecin.second){
                d[vecin.first] = d[nod] + vecin.second;

                if (!inQueue[vecin.first]){
                    q.push(vecin.first);
                    inQueue[vecin.first] = true;
                }
            }

            vizitat[vecin.first] ++;
        }
    }

    if (!q.empty())
        printf("Ciclu negativ!\n");
    else
        write();
}

int main(){
    read();
    solve();
    return 0;
}