#include <bits/stdc++.h> #define ff first #define ss second #define pb push_back #define all(x) x.begin(), x.end() #define rall(x) x.rbegin(), x.rend() #define int long long using namespace std; int a, b, c, d; main(){ ios_base::sync_with_stdio(0); cin.tie(0); int n, k; cin >> n >> k; vector <int> v(n + k), vis(n + k); map <int,int> mp; for(int i = 0; i < n + k; i++){ cin >> v[i]; mp[v[i]]++; } for(int l = 0; l < k; l++){ for(int r = n + k - 1; r >= (n + k - 1) - (k - l); r--){ int cnt = l + (n + k - 1) - r; for(int i = l; i <= r; i++){ if(!mp.count(v[l] + v[r] - v[i])){ cnt++; vis[i] = 0; }else{ vis[i] = 1; } } if(cnt == k){ //cout << "YES"; for(int j = l; j <= r; j++){ if(vis[j] == 1) cout << v[j] <<" "; } cout << endl; return 0; } } } }

tabletennis.cpp:13:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   13 | main(){
      | ^~~~