Cod sursa(job #2951129)

Utilizator radubuzas08Buzas Radu radubuzas08 Data 5 decembrie 2022 15:15:43
Problema Algoritmul Bellman-Ford Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.22 kb
#include <fstream>
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("Ofast")
using namespace std;

#define maxn 50001
#define maxm 250001
#define inf (1 << 62)

struct muchie
{
    long long from, to, cost;
} e[maxm];

long n, m, i, j, k, cost[maxn], tata[maxn];

void init()
{
    long long i;
    tata[1] = cost[1]=0;
    for(i=2; i<=n; i++) {
        cost[i] = inf;
        tata[i] = 0;
    }
}

void solve()
{
    long long i, j;
    for(i=1; i<n; i++)
        for(j=1; j<=m; j++)
            if(cost[e[j].from] + e[j].cost < cost[e[j].to]) {
                cost[e[j].to] = cost[e[j].from] + e[j].cost;
                tata[e[j].to] = e[j].from;
            }
}

bool check_negativ()
{
    for(long long i=1; i<=m; i++)
        if(cost[e[j].from] + e[j].cost < cost[e[j].to])
            return 1;
    return 0;
}

int main()
{
    ifstream in("bellmanford.in");
    ofstream out("bellmanford.out");

    in >> n >> m;
    for(i=1; i<=m; i++)
        in >> e[i].from >> e[i].to >> e[i].cost;

    in.close();
    init();
    solve();
    if(check_negativ())
    {
        out << "Ciclu negativ!\n";
        return 0;
    }
    for(i=2; i<=n; i++)
        out << cost[i] << ' ';
    out.close();
    return 0;
}