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#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <math.h>
#include <stdlib.h>
const char *in_file_name = "bellmanford.in";
const char *out_file_name = "bellmanford.out";
const int MAX = 9999999;
using namespace std;
ifstream in_file;
ofstream out_file;
int N, M;
int *dist, *cnt_in_queue;
vector<pair <int, int> > *edges;
vector<int> *edge;
bool *in_queue;
queue <int> Q;
void die(bool assertion, const char *message)
{
if (assertion) {
fprintf(stderr, "(%s, %d): ",__FILE__, __LINE__);
perror(message);
exit(EXIT_FAILURE);
}
}
void read_file()
{
/* N - noduri */
/* M - arce */
int from, to, cost;
in_file >> N >> M;
edges = new vector<pair <int, int> >[N+1];
edge = new vector<int>[N+1];
in_queue = new bool[N+1];
dist = new int[N+1];
cnt_in_queue = new int[N+1];
for (int i = 0; i < M; i++) {
in_file >> from >> to >> cost;
edges[from].push_back(make_pair(to, cost));
edge[from].push_back(to);
}
dist[1] = 0;
for (int i = 2; i <= N; i++)
dist[i] = MAX;
}
void bellman_ford()
{
int node, node2, cost;
bool negative_cycle = false;
int size;
while (!Q.empty() && !negative_cycle) {
node = Q.front();
Q.pop();
in_queue[node] = false;
size = edges[node].size();
for (int i = 0; i < size; i++) {
node2 = edges[node][i].first;
cost = edges[node][i].second;
if (dist[node2] > dist[node] + cost) {
dist[node2] = dist[node] + cost;
if (!in_queue[node2]) {
if (cnt_in_queue[node2] > N)
negative_cycle = true;
else {
Q.push(node2);
in_queue[node2] = true;
cnt_in_queue[node2]++;
}
}
}
}
}
if (negative_cycle) {
out_file << "Ciclu negativ!";
}
else {
for (int i = 2; i <= N; i++)
out_file << dist[i] << " ";
}
}
int main()
{
in_file.open(in_file_name, ios::in);
die(!in_file, "Error opening file for reading");
out_file.open(out_file_name, ios::out);
die(!out_file, "Error opening file for writing");
read_file();
in_queue[1] = true;
Q.push(1);
/* more like dijkstra */
bellman_ford();
in_file.close();
out_file.close();
delete []edges;
delete []edge;
delete []in_queue;
delete []dist;
delete []cnt_in_queue;
return 0;
}