Submission #65039

#	Time	Username	Problem	Language	Result	Execution time	Memory
65039		bazsi700	007 (CEOI14_007)	C++14	30 / 100	459 ms	15980 KiB

007

#include <bits/stdc++.h>

using namespace std;

int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    int n,m,s,d,a,b;
    cin >> n >> m >> s >> d >> a >> b;
    vector<vector<int> > graph(n+1,vector<int>());
    for(int i = 0; i < m; i++) {
        int x,y;
        cin >> x >> y;
        graph[x].push_back(y);
        graph[y].push_back(x);
    }
    vector<bool> wass(n+1,false);
    vector<int> dists(n+1,0);
    vector<bool> wasd(n+1,false);
    vector<int> distd(n+1,0);
    wass[s] = true;
    queue<int> q;
    q.push(s);
    while(!q.empty()) {
        int v = q.front();
        q.pop();
        for(int u : graph[v]) {
            if(!wass[u]) {
                wass[u] = true;
                q.push(u);
                dists[u] = dists[v]+1;
            }
        }
    }
    wasd[d] = true;
    q.push(d);
    while(!q.empty()) {
        int v = q.front();
        q.pop();
        for(int u : graph[v]) {
            if(!wasd[u]) {
                wasd[u] = true;
                q.push(u);
                distd[u] = distd[v]+1;
            }
        }
    }
    if(dists[a] == dists[b] && distd[a] == distd[b]) {
        cout << max(min(distd[a]-dists[a],distd[b]-dists[b])-1,-1);
    } else {
        cout << max(min(distd[a]-dists[a],distd[b]-dists[b]),-1);
    }
    return 0;
}

• Subtask 1: 9 / 30
• Subtask 2: 21 / 70