Submission #1042783

#	Time	Username	Problem	Language	Result	Execution time	Memory
1042783		AmirAli_H1	Counting Mushrooms (IOI20_mushrooms)	C++17	80.43 / 100	6 ms	600 KiB

mushrooms

// In the name of Allah

#include <bits/stdc++.h>
#include "mushrooms.h"
using namespace std;

typedef		long long int			ll;
typedef		long double				ld;
typedef		pair<int, int>			pii;
typedef		pair<ll, ll>			pll;
typedef		complex<ld>				cld;

#define		all(x)					(x).begin(),(x).end()
#define		len(x)					((ll) (x).size())
#define		F						first
#define		S						second
#define		pb						push_back
#define		sep						' '
#define		endl					'\n'
#define		Mp						make_pair
#define		kill(x)					cout << x << '\n', exit(0)
#define		set_dec(x)				cout << fixed << setprecision(x);
#define		file_io(x,y)			freopen(x, "r", stdin); freopen(y, "w", stdout);
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

const int maxn = 20000 + 4;
const int M = 141;
vector<int> ls[2], lsx;
int col[maxn];

int count_mushrooms(int n) {
	int j = 0, T = 0;
	while (j < n) {
		if (j + 1 >= n || max(len(ls[0]), len(ls[1])) <= 1) {
			if (j == 0) col[j] = 0;
			else if (use_machine({0, j}) == 1) col[j] = 1;
			else col[j] = 0;
			T = 1;
		}
		else {
			int R = 0;
			if (len(ls[1]) >= len(ls[0])) R = 1;
			int x = use_machine({ls[R][0], j, ls[R][1], j + 1});
			if (x == 0) col[j] = col[j + 1] = R;
			else if (x == 1) {
				col[j] = R; col[j + 1] = 1 - R;
			}
			else if (x == 2) {
				col[j] = 1 - R; col[j + 1] = R;
			}
			else col[j] = col[j + 1] = 1 - R;
			T = 2;
		}
		while (T--) {
			ls[col[j]].pb(j); j++;
		}
		if (max(len(ls[0]), len(ls[1])) >= M) break;
	}
	
	int res = len(ls[0]);
	if (n <= j) return res;
	
	int mx = max(len(ls[0]), len(ls[1]));
	for (int i = j; i < n; i += mx) {
		lsx.clear();
		for (int j = i; j < min(n, i + mx); j++) {
			lsx.pb(j);
			if (len(ls[0]) >= len(ls[1])) lsx.pb(ls[0][j - i]);
			else lsx.pb(ls[1][j - i]);
		}
		int t1 = (use_machine(lsx) + 1) / 2, t2 = (min(n, i + mx) - i) - t1;
		if (len(ls[0]) >= len(ls[1])) res += t2;
		else res += t1;
	}
	return res;
}

• Subtask 1: 80.427 / 100