Mai intai trebuie sa te autentifici.
Cod sursa(job #2034192)
Utilizator | Data | 7 octombrie 2017 16:15:47 | |
---|---|---|---|
Problema | BFS - Parcurgere in latime | Scor | 80 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.95 kb |
#include <iostream>
#include <set>
#include <queue>
#include <vector>
#define lim 100002
#define INF 0x3f3f3f3f
using namespace std;
queue <int> Q;
set <int> G[lim];
vector <int> D;
int n, m, S;
void Read()
{
cin >> n >> m >> S;
D.resize(n+1, INF);
int x, y;
for(; m; --m)
{
cin >> x >> y;
G[x].insert(y);
}
}
void Read_Out()
{
for(int i = 1; i < D.size(); ++i)
if(D[i] == INF) cout << -1 << " ";
else
cout << D[i] << " ";
}
void BFS()
{
while(!Q.empty())
{
int F = Q.front();
Q.pop();
for(set <int> :: iterator it = G[F].begin(); it != G[F].end(); ++it)
if(D[*it] == INF)
{
D[*it] = D[F] + 1;
Q.push(*it);
}
}
}
int main()
{
freopen("bfs.in" , "r", stdin);
freopen("bfs.out", "w", stdout);
Read();
D[S] = 0;
Q.push(S);
BFS();
Read_Out();
}