Submission #1060492

#	Time	Username	Problem	Language	Result	Execution time	Memory
1060492		Mihailo	Counting Mushrooms (IOI20_mushrooms)	C++17	78.75 / 100	8 ms	600 KiB

mushrooms

#include <cstdio>
#include <cstdlib>
#include <cstdarg>
#include <bits/stdc++.h>
#define mp make_pair
#define pb push_back
#define xx first
#define yy second
#define pll pair<long long, long long>
#define MOD 1000000007
typedef long long ll;
using namespace std;
mt19937 mt(time(nullptr));
 
int use_machine(vector<int> x);
ll N, reached, sol;
vector<ll> A, B;
 
ll next() {
	return reached++;
}
 
void identifyA() {
	vector<int> v;
	ll rez;
	while(A.size()<120&&B.size()<120) {
		v.clear();
		v.pb(A[0]);
		v.pb(next());
		v.pb(A[1]);
		v.pb(next());
		rez=use_machine(v);
		if(rez&1) {
			B.pb(reached-1);
		}
		else {
			A.pb(reached-1);
		}
		if(rez&2) {
			B.pb(reached-2);
		}
		else {
			A.pb(reached-2);
		}
	}
}
 
void identifyB() {
	vector<int> v;
	ll rez;
	while(A.size()<120&&B.size()<120) {
		v.clear();
		v.pb(B[0]);
		v.pb(next());
		v.pb(B[1]);
		v.pb(next());
		rez=use_machine(v);
		if(rez&1) {
			A.pb(reached-1);
		}
		else {
			B.pb(reached-1);
		}
		if(rez&2) {
			A.pb(reached-2);
		}
		else {
			B.pb(reached-2);
		}
	}
}
 
void testA() {
	vector<int> v;
	sol=A.size();
	while(reached<N) {
		v.clear();
		v.pb(A[0]);
		for(int i=1; i<A.size()&&reached<N; i++) {
			v.pb(next());
			v.pb(A[i]);
		}
		sol+=(v.size()-use_machine(v))/2;
	}
}
 
void testB() {
	vector<int> v;
	sol=B.size();
	while(reached<N) {
		v.clear();
		v.pb(B[0]);
		for(int i=1; i<B.size()&&reached<N; i++) {
			v.pb(next());
			v.pb(B[i]);
		}
		sol+=(v.size()-use_machine(v))/2;
	}
}
 
int count_mushrooms(int _N) {
	N=_N;
	vector<int> v;
	if(N<240) {
		sol=1;
		for(int i=1; i<N; i++) {
			v.clear();
			v.pb(0);
			v.pb(i);
			if(!use_machine(v)) sol++;
		}
		return sol;
	}
	A.pb(0);
	v.pb(0);
	v.pb(1);
	if(use_machine(v)) {
		B.pb(1);
		v.pb(2);
		reached=3;
		if(use_machine(v)==1) {
			B.pb(2);
			identifyB();
		}
		else {
			A.pb(2);
			identifyA();
		}
	}
	else {
		reached=2;
		A.pb(1);
		identifyA();
	}
	if(A.size()>B.size()) {
		testA();
	}
	else {
		testB();
		sol=N-sol;
	}
	return sol;
}

Compilation message (stderr)

mushrooms.cpp: In function 'void testA()':
mushrooms.cpp:79:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   79 |   for(int i=1; i<A.size()&&reached<N; i++) {
      |                ~^~~~~~~~~
mushrooms.cpp: In function 'void testB()':
mushrooms.cpp:93:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   93 |   for(int i=1; i<B.size()&&reached<N; i++) {
      |                ~^~~~~~~~~

• Subtask 1: 78.7456 / 100