Cod sursa(job #826439)

Utilizator zalmanDanci Emanuel Sebastian zalman Data 30 noiembrie 2012 18:23:37
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.9 kb
#include <cstdio>
#include <vector>
#include <queue>
#include <cstring>
#define NMAX 100005
using namespace std;

int N, M, S, dist[NMAX];
vector<int> G[NMAX];
queue<int> q;

void read(void)
{
	int x, y;
	FILE *f = fopen("bfs.in", "r");
		
	fscanf(f, "%d%d%d", &N, &M, &S);	
	for(int i = 0; i < M ; ++i)	
		fscanf(f, "%d%d", &x, &y),
		G[x].push_back(y);
		
	fclose(f);
}
void BFS(void) 
{
	memset(dist, -1, (N+1) * sizeof(int));
	dist[S] = 0;
	q.push(S);
	
	while(!q.empty())
	{
		int nod = q.front();
		q.pop();
		
		for(int i = 0; i < G[nod].size(); ++i)
		{
			int adiacNod = G[nod][i];
			if(dist[adiacNod] == -1)
				q.push(adiacNod),
				dist[adiacNod] = dist[nod] + 1;
		}
	}
}

void print(void)
{
	FILE *g = fopen("bfs.out", "w");
	for(int i = 1; i <= N; ++i)
		fprintf(g, "%d ", dist[i]);
	
	fclose(g);
}
int main(void)
{
	read();
	BFS();
	print();
}