Cod sursa(job #1980353)

Utilizator codeThatBitDaniel-Florin Dosaru codeThatBit Data 12 mai 2017 22:21:02
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.84 kb
#include <assert.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <list>
#include <queue>
using namespace std;

#define FILE_IN "bfs.in"
#define FILE_OUT "bfs.out"

#define ALB 0
#define GRI 1
#define NEGRU 2

void bfs(vector<vector<int> > &graph, int source, FILE * fout) {
    //int p[graph.size()];
    int dist[graph.size()];
    int color[graph.size()];
    for (int i = 0; i < (int) graph.size() ; i++) {
        //p[i] = -1;
        dist[i] = -1;
        color[i] = ALB;
    }

    dist[source] = 0;
    color[source] = GRI;
    queue<int> q;
    q.push(source);

    while (!q.empty()){
        int u = q.front();
        q.pop();
        for (int i = 0; i < (int)graph[u].size(); i++) {
            int v = graph[u][i];
            if(color[v] == ALB) {
                dist[v] = dist[u] + 1;
                //p[v] = u;
                color[v] = GRI;
                q.push(v);
            }
        }
        color[u] = NEGRU;
    }
    for (int i = 1; i < (int) graph.size() ; i++) {
        fprintf(fout, "%d ", dist[i]);
    }
    //printf("\n");
}

int main() {
    int N = 0, M = 0, S = 0;

    FILE * fin = fopen(FILE_IN, "r");
    FILE * fout = fopen(FILE_OUT, "w");

    assert(fin != NULL);
    assert(fout != NULL);
    assert(fscanf(fin, "%d %d %d\n", &N, &M, &S) == 3);
    vector<vector<int> > graph;

    for (int i = 0; i <= N; i++) {
        vector<int> v;
        graph.push_back(v);
    }

    for (int i = 0; i < M; i++) {
        int u, v;
        assert(fscanf(fin, "%d %d\n", &u, &v) == 2);
        graph[u].push_back(v);
    }

    // for (int i = 1; i <= N; i++) {
    //     printf("%d: ", i);
    //     for (int j = 0; j <(int) graph[i].size(); j++) {
    //         printf("%d, ", graph[i][j]);
    //     }
    //     printf("\n");
    // }
    bfs(graph, S, fout);


    fclose(fin);
    fclose(fout);
    return 0;
}