Submission #832335

#	Time	Username	Problem	Language	Result	Execution time	Memory
832335		penguinman	Carnival Tickets (IOI20_tickets)	C++17	11 / 100	3074 ms	7196 KiB

tickets

#include "tickets.h"
#include <bits/stdc++.h>
 
using std::cin;
using std::cout;
using std::endl;
using std::vector;
using std::string;
using ll = long long;
using vi = vector<ll>;
using vii = vector<vi>;
using pii = std::pair<ll,ll>;
 
#define ln "\n"
#define rep(i,j,k) for(ll i=ll(j); i<ll(k); i++)
#define REP(i,j,k) for(ll i=ll(j); i<=ll(k); i++)
#define per(i,j,k) for(ll i=ll(j); i>=ll(k); i--)
#define pb emplace_back
#define mp std::make_pair
#define mtp std::make_tuple
#define all(a) a.begin(),a.end()

constexpr ll inf = (1ll<<60);
 
long long find_maximum(int k, std::vector<std::vector<int>> x) {
	ll N = x.size();
	ll M = x[0].size();
	vector<vector<int>> ans_allocate(N,vector<int>(M,-1));
	ll final_ans = -inf;
	REP(half,0,N*M){
		vector<std::tuple<ll,ll,ll>> data;
		rep(i,0,N){
			rep(j,0,M) data.pb(mtp(x[i][j],i,j));
		}
		sort(all(data));
		ll ans = 0;
		vii left(N), right(N);
		rep(i,0,half){
			ll val, I,J; std::tie(val, I,J) = data[i];
			left[I].pb(J);
		}
		rep(i,half,N*M){
			ll val, I,J; std::tie(val, I,J) = data[i];
			right[I].pb(J);
		}
 
		vii use_left(N), use_right(N);
		ll goal = N*k/2;
		ll current = 0;
		std::priority_queue<pii> que;
		rep(i,0,N){
			rep(j,left[i].size(),k){
				use_right[i].pb(right[i].back());
				right[i].pop_back();
				current++;
			}
			while(left[i].size() > k) left[i].pop_back();
			if(right[i].empty() || left[i].empty()) continue;
			que.push(mp(x[i][right[i].back()]+x[i][left[i].back()], i));
		}
 
		/*rep(i,0,N){
			cout << "! " << i << ln;
			for(auto el: left[i]) cout << el << " ";
			cout << ln;
			for(auto el: use_right[i]) cout << el << " ";
			cout << ln;
		}*/
 
		while(current < goal){
			if(que.empty()) break;
			auto el = que.top(); que.pop();
			ll i = el.second;
			left[i].pop_back();
			use_right[i].pb(right[i].back());
			right[i].pop_back();
			current++;
			if(right[i].empty() || left[i].empty()) continue;
			que.push(mp(x[i][right[i].back()]+x[i][left[i].back()], i));
		}

		if(current != goal) continue;
 
		use_left = left;
 
		vector<vector<int>> allocate(N,vector<int>(M,-1));
		vector<pii> cnt(k);
		rep(i,0,k) cnt[i] = mp(0,i);
		rep(i,0,N){
			sort(all(cnt));
			ll idx = 0;
			for(auto el: use_left[i]){
				allocate[i][el] = cnt[idx].second;
				cnt[idx].first++;
				idx++;
				//cout << x[i][el] << " ";
				ans -= x[i][el];
			}
			for(auto el: use_right[i]){
				allocate[i][el] = cnt[idx].second;
				cnt[idx].first--;
				idx++;
				ans += x[i][el];
				//cout << " " << x[i][el];
			}
			//cout << ln;
		}
		//cout << ans << ln;
		if(ans > final_ans){
			final_ans = ans;
			ans_allocate = allocate;
		}
	}
	allocate_tickets(ans_allocate);
	return final_ans;
}

Compilation message (stderr)

tickets.cpp: In function 'long long int find_maximum(int, std::vector<std::vector<int> >)':
tickets.cpp:57:25: warning: comparison of integer expressions of different signedness: 'std::vector<long long int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   57 |    while(left[i].size() > k) left[i].pop_back();
      |          ~~~~~~~~~~~~~~~^~~

• Subtask 1: 11 / 11
• Subtask 2: 0 / 16
• Subtask 3: 0 / 14
• Subtask 4: 0 / 14
• Subtask 5: 0 / 12
• Subtask 6: 0 / 23
• Subtask 7: 0 / 10