Submission #365754

#	Time	Username	Problem	Language	Result	Execution time	Memory
365754		tengiz05	Table Tennis (info1cup20_tabletennis)	C++17	58 / 100	3105 ms	564828 KiB

tabletennis

#include <bits/stdc++.h>
using namespace std;
//~ #define int long long
#define FASTIO ios_base::sync_with_stdio(false); cin.tie(NULL);
#define all(x) (x).begin(), (x).end()
#define pb push_back
#define pii pair<int, int>
#define ff first
#define ss second
#define PI acos(-1)
#define ld long double
template<class T> bool chmin(T& a, const T& b) {return a>b? a=b, true:false;}
template<class T> bool chmax(T& a, const T& b) {return a<b? a=b, true:false;}
const int mod = 1e9+7, N = 2e5+5;
int msb(int val){return sizeof(int)*8-__builtin_clzll(val)-1;}
int n, m, k;
int a[N];
bool check(vector<int> &v){
	int n = v.size();
	int t = v[0] + v[n-1];
	for(int l=0,r=n-1;l<r;l++,r--){
		if(v[l] + v[r] != t)return false;
	}return true;
}
void solve(int test_case){
	int i, j;
	cin >> n >> k;
	m = n+k;
	for(i=1;i<=m;i++){
		cin >> a[i];
	}
	sort(a+1,a+m+1);
	if(k == 1){
		bool ok = true;
		int t = (a[1] + a[m-1]);
		for(int l=1,r=m-1;l<r;l++,r--){
			if(a[l] + a[r] != t)ok = false;
		}
		if(ok){
			for(i=1;i<=m-1;i++)cout << a[i] << ' ' ;
			cout << '\n';
			return;
		}
		ok = true;
		t = (a[2] + a[m]);
		for(int l=2,r=m;l<r;l++,r--){
			if(a[l] + a[r] != t)ok = false;
		}
		
		if(ok){
			for(i=2;i<=m;i++)cout << a[i] << ' ' ;
			cout << '\n';
			return;
		}
		t = a[1] + a[m];
		for(int l=2,r=m-1;l<r;l++,r--){
			if(a[l] + a[r] != t){
				vector<int> v;
				for(i=1;i<=m;i++){
					if(i==l)continue;
					v.pb(a[i]);
				}
				if(check(v)){
					for(auto x : v)cout << x << ' ' ;
					cout << '\n';
					return;
				}
				v.clear();
				for(i=1;i<=m;i++){
					if(i==r)continue;
					v.pb(a[i]);
				}
				if(check(v)){
					for(auto x : v)cout << x << ' ' ;
					cout << '\n';
					return;
				}
				assert(false);
			}
		}
	}else {
		map<int,int> possible_sums_not;
		for(i=1;i<=m;i++){
			for(j=i+1;j<m;j++){
				possible_sums_not[a[i] + a[j]]++;
			}
		}
		vector<pii> possible_sums;
		for(auto [x,y] : possible_sums_not)possible_sums.pb({y,x});
		sort(all(possible_sums));
		reverse(all(possible_sums));
		//~ mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
		//~ shuffle(all(possible_sums), rng);
		for(auto [no_need, sum] : possible_sums){
			unordered_map<int,int>cnt;
			for(i=1;i<=m;i++){
				cnt[a[i]]++;
			}
			int have = 0;
			vector<int> v;
			for(i=1;i<=m;i++){
				if(cnt[a[i]] <= 0)continue;
				if(a[i] >= sum)continue;
				if(sum-a[i] == a[i]){
					if(cnt[sum - a[i]] > 1){
						cnt[sum - a[i]]--;
						cnt[a[i]]--;
						have++;
						v.pb(a[i]);
						v.pb(sum-a[i]);
					}
				}else if(cnt[sum - a[i]] > 0){
					cnt[sum - a[i]]--;
					cnt[a[i]]--;
					have++;
					v.pb(a[i]);
					v.pb(sum-a[i]);
				}
			}
			//~ cout << sum << ' ' << have << '\n';
			if(have >= n/2){
				sort(v.begin(), v.begin() + n);
				for(i=0;i<n;i++)cout << v[i] << ' ' ;
				cout << '\n';
				return;
			}
		}
	}
	return;
}
/*

4 1
2 4 8 6 10

*/
signed main(){
	FASTIO;
//~ #define MULTITEST 1
#if MULTITEST
	int _T;
	cin >> _T;
	for(int T_CASE = 1; T_CASE <= _T; T_CASE++)
		solve(T_CASE);
#else
	solve(1);
#endif
	return 0;
}

• Subtask 1: 11 / 11
• Subtask 2: 9 / 9
• Subtask 3: 0 / 14
• Subtask 4: 15 / 15
• Subtask 5: 9 / 9
• Subtask 6: 14 / 14
• Subtask 7: 0 / 15
• Subtask 8: 0 / 13