Pagini recente » Cod sursa (job #10325) | Cod sursa (job #2839644) | Cod sursa (job #1648677) | Cod sursa (job #1024901) | Cod sursa (job #1502898)
#include <iostream>
#include <fstream>
#include <vector>
#include <queue>
using namespace std;
#define nmax 100001
#define inf 1<<30
ifstream fi("bfs.in");
ofstream fo("bfs.out");
int n, m, s;
int a, b;
int Cost[nmax];
vector <int> G[nmax];
queue < pair<int, int> > q;
void read()
{
fi >> n >> m >> s;
for (int i = 1; i <= m; i++)
{
fi >> a >> b;
G[a].push_back(b);
}
}
void init()
{
q.push(make_pair(s, 0));
for (int i = 1; i <= n; i++)
Cost[i] = inf;
Cost[s] = 0;
}
void bfs()
{
init();
while (!q.empty())
{
int nodulCurent = q.back().first;
int costulCurent = q.back().second;
q.pop();
for (int i = 0; i < G[nodulCurent].size(); i++)
{
int vecin = G[nodulCurent][i];
if (Cost[vecin] > costulCurent + 1)
{
Cost[vecin] = costulCurent + 1;
q.push(make_pair(vecin, Cost[vecin]));
}
}
}
}
void write()
{
for (int i = 1; i <= n; i++)
{
if (Cost[i] == inf)
Cost[i] = -1;
fo << Cost[i] << " ";
}
}
int main()
{
read();
bfs();
write();
return 0;
}