Submission #490305

#	Time	Username	Problem	Language	Result	Execution time	Memory
490305		mraron	Packing Biscuits (IOI20_biscuits)	C++14	100 / 100	945 ms	1608 KiB

biscuits

#include "biscuits.h"
#include <iostream>
#include <unordered_map>
#include <map>
#include <utility>
#include <functional>
#include <cassert>
#include <set>
#include <random>
using namespace std;

using ll = long long ;

ll x;
vector<ll> a;

map<ll, ll> dp[61];

mt19937 rnd(453);

ll calc(ll rem, ll i) {
	if(i>=(int)a.size()) return 1LL<<(rem/x);
	
	auto it=dp[i].lower_bound(rem);
	if(it!=dp[i].end() && it->first==rem) return dp[i][rem];
	
	if(it!=dp[i].end() && it!=dp[i].begin()) {
		if(it->second==prev(it)->second) {
			return it->second;
		}
	}
	
	ll orig=rem;
	if(i<(int)a.size() || rem>=x) {
		if(i<(int)a.size()) {
			rem+=a[i];
		}
		
		ll ans=0;
		
		if(rem>=x) {
			if(i&1) {
				ans+=calc(rem/2, i+1);
				ans+=calc((rem-x)/2, i+1);
			}else {
				ans+=calc((rem-x)/2, i+1);
				ans+=calc(rem/2, i+1);
			}
		}else {
			ans+=calc(rem/2, i+1);
		}
		
		return dp[i][orig]=ans;
	}else {
		return 1;
	}
}	

ll count_tastiness(ll x_, vector<ll> a_) {	
	a=a_;
	x=x_;

	a.resize(60);
	for(int i=0;i<60;++i) {
		if(a[i]>=x+2) {
			ll diff=a[i]-(x+1);
			a[i]-=(diff+1)/2*2;
			a[i+1]+=(diff+1)/2;
		}
	}
	
	while(a.back()==0) a.pop_back();
	
	for(auto& i:dp) i.clear();
	
	return calc(0, 0);
}

• Subtask 1: 9 / 9
• Subtask 2: 12 / 12
• Subtask 3: 21 / 21
• Subtask 4: 35 / 35
• Subtask 5: 23 / 23