Submission #465770

#	Time	Username	Problem	Language	Result	Execution time	Memory
465770		AmirElarbi	Senior Postmen (BOI14_postmen)	C++14	0 / 100	6 ms	2960 KiB

postmen

#include <bits/stdc++.h>
#define vi vector<int>
#define ve vector
#define ll long long
#define vf vector<float>
#define vll vector<pair<ll,ll>>
#define ii pair<int,int>
#define vvi vector<vi>
#define vii vector<ii>
#define gii greater<ii>
#define pb push_back
#define fi first
#define se second
#define INF 1e7
#define unsigned u
#define eps 1e-18
#define eps1 1e-25
#define optimise ios_base::sync_with_stdio(false);cin.tie(NULL);
#define MAX_A 100005
#define V 450
#define re register
#define maxi(a,b) ((a) > (b) ? (a) : (b))
using namespace std;
vii adj[100005];
bool vis[100005];
int tv[100005];
int n,m,used, tours = 1;
bool dfs(int u, int p, int start){
    //cout << u << " " << start << " " << used << " " << tours << endl;
    tv[u]++;
    for(auto x : adj[u])
    {
        
        if(x.fi == p)
            continue;
        if(vis[x.se])
            continue;
        if(x.fi == start)
        {
            vis[x.se] = true;
            used++;
            if(used == m)
                return true;
            for (int i = 1; i <= n; ++i)
            {
                //cout << i << endl;
                tours++;
                if(dfs(i,-1,i)){
                    cout  << i << endl;
                    return true;
                }
                tours--;
            }
            vis[x.se] = 0;
            used--;
            return false;
        }
        if(tv[x.fi] >= tours)
            continue;
        vis[x.se] = true;
        used++;
        if(dfs(x.fi,u,start)){
            cout << x.fi << " ";
            return true;
        }

        vis[x.se] = 0;
        used--;
    }
    return false;
}
int main(){
    optimise;
    cin >> n >> m;
    for (int i = 0; i < m; ++i)
    {
        int a,b;
        cin >> a >>b;
        adj[a].pb({b,i});
        adj[b].pb({a,i});
    }
    if(dfs(1,-1,1)){
        cout << 1;
        return 0;
    }
}

• Subtask 1: 0 / 38
• Subtask 2: 0 / 17
• Subtask 3: 0 / 45