Submission #414041

#	Time	Username	Problem	Language	Result	Execution time	Memory
414041		cfalas	Counting Mushrooms (IOI20_mushrooms)	C++14	92.24 / 100	11 ms	432 KiB

mushrooms

#include "mushrooms.h"
#include<bits/stdc++.h>
using namespace std;
#define mp make_pair
#define INF 10000000
#define MOD 1000000007
#define MID ((l+r)/2)
#define HASHMOD 2305843009213693951
#define ll long long
#define ull unsigned long long
#define F first
#define S second
typedef pair<ll, ll> ii;
typedef pair<ii, int> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef map<int, int> mii;

#define EPS 1e-6
#define FOR(i,n) for(int i=0;i<((int)(n));i++)
#define FORi(i,a,b) for(int i=((int)(a));i<((int)(b));i++)
#define FOA(v, a) for(auto v : a)

#define BLOCK 90

int count_mushrooms(int n) {
	int ans=1;
	vi a;
	vi b;
	a.push_back(0);
	int last=0;
	FORi(i,1,n){
		if(a.size()>=BLOCK || b.size()>=BLOCK) break;
		if((a.size()<2 && b.size()<2) || i+1>=n){
			int x = use_machine({0,i});
			if(x) b.push_back(i);
			else a.push_back(i), ans++;
		}
		else{
			vi c;
			if(a.size()>=2) c = a;
			else c = b;
			int x = use_machine({c[0], i, c[1], i+1});
			int cur=0;
			if(a.size()<2) x = 3-x;
			if(x==0) a.push_back(i), a.push_back(i+1), cur+=2;
			else if(x==1) a.push_back(i), b.push_back(i+1), cur++;
			else if(x==2) b.push_back(i), a.push_back(i+1), cur++;
			else if(x==3) b.push_back(i), b.push_back(i+1);
			ans+=cur;
			i++;
		}
		last = i;
	}
	vi c;
	FORi(i,last+1,n){
		if(a.size()>=b.size()) c = a;
		else c = b;

		vi m;
		FOR(j,c.size()){
			if(i+j>=n) break;
			m.push_back(c[j]), m.push_back(i+j);
		}
		int u = m.size()/2;
		int x = use_machine(m);

		if(a.size()==c.size()) ans+=u - (x+1)/2;
		else ans+=(x+1)/2;
		i+=u-1;

		if(a.size()>=b.size() && x%2==0) a.push_back(i);
		else if(a.size()>=b.size() && x%2==1) b.push_back(i);
		else if(a.size()<b.size() && x%2==1) a.push_back(i);
		else if(a.size()<b.size() && x%2==0) b.push_back(i);

	}
	return ans;
}

• Subtask 1: 92.2449 / 100