Cod sursa(job #1913173)

Utilizator adiXMGemene Adrian adiXM Data 8 martie 2017 12:02:46
Problema BFS - Parcurgere in latime Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.91 kb
#include <bits/stdc++.h>

using namespace std;
ifstream f("bfs.in");
ofstream g("bfs.out");
const int nMax = 100003;
const int inf = 1e9;
int dp[nMax], n, m ,s;
queue <int> Q;
vector <int> Graf[nMax];
inline void Bfs(int start) {
    for(int i = 1; i <= n; i++) {
        dp[i] = inf;
    }
    dp[start] = 0;
    Q.push(start);
    while(!Q.empty()) {
        int nod = Q.front();
        Q.pop();
        for(const auto &i : Graf[nod]) {
            if(dp[i] > dp[nod] + 1) {
                dp[i] = dp[nod] + 1;
                Q.push(i);
            }
        }
    }
}
int main()
{
    int x, y;
    f >> n >> m >> s;
    for(int i = 1; i <= m; i++){
        f >> x >> y;
        Graf[x].push_back(y);
    }
    Bfs(s);
    for(int i = 1; i <= n; i++) {
        if(dp[i] == inf) {
            g << "-1 ";
            continue;
        }
        g << dp[i] << " ";
    }
    return 0;
}