Submission #1182244

#	Time	Username	Problem	Language	Result	Execution time	Memory
1182244		kl0989e	Flight to the Ford (BOI22_communication)	C++20	70 / 100	1212 ms	3252 KiB

communication

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

#pragma GCC optimize("Ofast")

#define ll long long
#define fi first
#define se second
#define pb push_back
#define vi vector<int>
#define vl vector<ll>
#define pi pair<int, int>
#define pl pair<ll,ll>
#define all(x) (x).begin(),(x).end()

vi nums={0b0000,0b0110,0b1001,0b1111};

set<int> valid={0b0000,0b0001,0b0010,0b0100,0b0101,0b1000,0b1001,0b1010};

pi get(int a) {
	pi ret={-1,-1};
	for (int i=0; i<4; i++) {
		if (valid.count(a^nums[i])) {
			if (ret.fi==-1) {
				ret.fi=i;
			}
			else {
				ret.se=i;
			}
		}
	}
	return ret;
}

int s(int a) {
	int ret=0;
	for (int i=0; i<4; i++) {
		ret=(ret<<1)+send((nums[a]&(1<<i))>0);
	}
	return ret;
}

int rec() {
	int ret=0;
	for (int i=0; i<4; i++) {
		ret=(ret<<1)+receive();
	}
	return ret;
}

void encode(int n, int x) {
	int lst=x&1;
    for (int i=1; i<=30; i++) {
		int sen=lst+2*((x&(1<<i))>0);
		int temp=s(sen);
		pi t=get(temp);
		lst=(t.se==sen);
	}
}

pi decode(int n) {
	vi a={0,1};
	for (int i=1; i<=30; i++) {
		int temp=rec();
		pi t=get(temp);
		vi ta={0,0};
		ta[0]=a[t.fi&1];
		if (t.fi&2) {
			ta[0]|=(1<<i);
		}
		ta[1]=a[t.se&1];
		if (t.se&2) {
			ta[1]|=(1<<i);
		}
		swap(a,ta);
	}
	return {max(1,min(n,a[0])),max(1,min(n,a[1]))};
}

• Subtask 1: 15 / 15
• Subtask 2: 55 / 85