Submission #1141598

#	Time	Username	Problem	Language	Result	Execution time	Memory
1141598		tkm_algorithms	DEL13 (info1cup18_del13)	C++20	0 / 100	830 ms	1020 KiB

del13

/**
*    In the name of Allah
*    We are nothing and you're everything
*    author: najmuddin
**/
 
#include <bits/stdc++.h>
#pragma GCC optimize("O3")
#pragma GCC target("avx2")
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("no-stack-protector")
#pragma GCC optimize("fast-math")
#pragma GCC optimize("trapv")
#pragma GCC optimize("inline")
using namespace std;
 
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
#define int ll
 
const char nl = '\n';
const int N = 1e8+5;
//const int inf = 1e18;
const int mod = 1e9+7;

void solve() {
	int n, m;
	cin >> n >> m;
	
	if ((n-m)%2 ==1) {
		cout << -1 << nl;
		return;
	} 
	
	map<int, int> mp, mp2;
	vector<int> b;
	for (int i = 0; i < m; ++i) {
		int x; cin >> x;
		b.push_back(x);
		mp[x] = 1;
	}
	
	vector<int> a;
	for (int i = 1; i <= n; ++i) {
		if (mp[i] != 1)mp2[i] = 1;
	}
	
	vector<int> ans;
	for (int i = 1; i <= n; ++i) {
		if (mp2[i] == 1 && mp2[i+2] == 1 && (mp2[i+1] == 1 || mp[i+1] == 1)) {
			mp2[i] = mp2[i+2] = 0;	
			ans.push_back(i+1);
		}
		if (mp2[i] == 1)a.push_back(i);
	}
	
	if (int(ans.size()) != (n - m) / 2) {
      cout << -1 << nl;
      return;
   }
	
	cout << sz(ans) << nl;
	for (auto j: ans)cout << j << ' ';
	cout << nl;
}
 
int32_t main() {
    ios::sync_with_stdio(0);
    cin.tie(0);
	
	int t = 1;
	cin >> t;
	
	while (t--) {
		solve();
	}
    return 0;
}

• Subtask 1: 0 / 15
• Subtask 2: 0 / 15
• Subtask 3: 0 / 15
• Subtask 4: 0 / 25
• Subtask 5: 0 / 30