제출 #465750

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
465750		AmirElarbi	어르신 집배원 (BOI14_postmen)	C++14	0 / 100	3 ms	460 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;
set<int> adj[2005];
bool vis[2005][2005];
int n,m,used;
bool dfs(int u, int p, int start){
    //cout << u << " " << start << " " << used << endl;
    for(auto x : adj[u])
    {
        //cout << adj[u].size() << endl;
        if(x == p)
            continue;
        if(vis[u][x])
            continue;
        vis[u][x] = true;
        vis[x][u] = true;
        used++;
        if(x == start)
        {
            if(used == m)
                return true;
            for (int i = 1; i <= n; ++i)
            {
                //cout << i << endl;
                //memset(vis, 0, sizeof vis);
                
                if(dfs(i,-1,i)){
                    cout  << i << endl;
                    return true;
                }
            }
            vis[u][x] = 0;
            vis[x][u] = 0;
            used--;
            return false;
        }
        if(dfs(x,u,start)){
            cout << x << " ";
            return true;
        }
        vis[u][x] = false;
        vis[x][u] = false;
        used--;
    }
    return false;
}
int main(){
    optimise;
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    #endif
    cin >> n >> m;
    for (int i = 0; i < m; ++i)
    {
        int a,b;
        cin >> a >>b;
        adj[a].insert(b);
        adj[b].insert(a);
    }
    for (int i = 1; i <= n; ++i)
    {
        used = 0;
        if(dfs(i,-1,i)){
            cout << i;
            return 0;
        }
    }
}

컴파일 시 표준 에러 (stderr) 메시지

postmen.cpp: In function 'int main()':
postmen.cpp:71:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   71 |         freopen("input.txt", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
postmen.cpp:72:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   72 |         freopen("output.txt", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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