Submission #1031970

#	Time	Username	Problem	Language	Result	Execution time	Memory
1031970		hotboy2703	Counting Mushrooms (IOI20_mushrooms)	C++17	79.30 / 100	7 ms	600 KiB

mushrooms

#include "mushrooms.h"
#include<bits/stdc++.h>
using namespace std;
using ll = int;
#define pll pair <ll,ll>
#define fi first
#define se second
#define MP make_pair
#define sz(a) (ll((a).size()))
#define BIT(mask,i) (((mask) >> (i))&1)
#define MASK(i) (1LL<<(i))
ll use(vector <ll> tmp){
	return use_machine(tmp);
}
int count_mushrooms(int n) {
	if (n==2){
		return 2 - use({0,1});
	}
	vector <ll> c[2];
	c[0].push_back(0);
	c[use({0,1})].push_back(1);
	c[use({0,2})].push_back(2);
	ll ptr = 3;
	ll res = 0;
	while (ptr < n){
		if (max(sz(c[0]),sz(c[1])) >= 120){
			ll id = 0;
			if (sz(c[1]) > sz(c[0]))id = 1;
			vector <ll> tmp;
			for (ll j = 0;j < sz(c[id]) && ptr < n;j ++,ptr++){
				tmp.push_back(c[id][j]);
				tmp.push_back(ptr);
			}
			ll cur = use(tmp);
			cur = cur/2+cur%2;
			if (id==1)res += cur;
			else res += sz(tmp)/2 - cur;
		}
		else{
			if (ptr + 1 < n){
				if (sz(c[0]) >= 2){
					ll tmp = use({ptr,c[0][0],ptr+1,c[0][1]});
					c[BIT(tmp,0)].push_back(ptr);
					c[BIT(tmp,1)].push_back(ptr+1);
				}
				else{
					ll tmp = use({ptr,c[1][0],ptr+1,c[1][1]});
					c[1-BIT(tmp,0)].push_back(ptr);
					c[1-BIT(tmp,1)].push_back(ptr+1);
				}
				ptr+=2;
			}
			else{
				c[use({0,ptr})].push_back(ptr);
				ptr++;
			}
		}
	}
	res += sz(c[0]);
	return res;
}

• Subtask 1: 79.2982 / 100