oj.uz

답안 #695273

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
695273 2023-02-04T21:20:11 Z finn__ Flight to the Ford (BOI22_communication) C++17
0 / 100
 444 ms 284 KB 
#include <bits/stdc++.h>
#include "communication.h"
using namespace std;

// 0 -> 0000, 1 -> 0110, 2 -> 1001, 3 -> 1111
int e[4] = {0, 6, 9, 15};
pair<int, int> d[16] = {{0, 2},
                        {0, 2},
                        {0, 1},
                        {1, 2},
                        {0, 1},
                        {0, 3},
                        {1, 3},
                        {1, 3},
                        {0, 2},
                        {0, 2},
                        {0, 3},
                        {2, 3},
                        {1, 2},
                        {2, 3},
                        {1, 3},
                        {1, 3}};

int bit_reverse(int X)
{
    int Y = 0;
    for (unsigned i = 0; i < 30; i++)
        Y |= ((X >> i) & 1) << (30 - i - 1);
    return Y;
}

void encode(int N, int X) // Send exactly 120 bits to encode any message.
{
    X = bit_reverse(X);
    for (unsigned i = 0; i < 30; i++)
    {
        int Y = e[X & 3], Z = 0;
        for (unsigned j = 0; j < 4; j++)
            Z = (Z << 1) | send(Y & 1), Y >>= 1;

        X >>= 2;
        X = (X << 1) | (int)(d[Z].second == Y);
    }
}

pair<int, int> get_interval(pair<int, int> p, pair<int, int> q, int i)
{
    switch (i)
    {
    case 0:
        return {p.first, (p.first + p.second) / 2};
    case 1:
        return {(p.first + p.second) / 2, p.second};
    case 2:
        return {q.first, (q.first + q.second) / 2};
    case 3:
        return {(q.first + q.second) / 2, q.second};
    default:
        assert(0);
    }
}

std::pair<int, int> decode(int N)
{
    pair<int, int> p = {0, 1 << 15}, q = {1 << 15, 1 << 30};
    for (unsigned i = 0; i < 30; i++)
    {
        int Y = 0;
        for (unsigned j = 0; j < 4; j++)
            Y = (Y << 1) | receive();

        pair<int, int> r = get_interval(p, q, d[Y].first);
        q = get_interval(p, q, d[Y].second);
        p = r;
    }
    return {p.first, q.first};
}

Subtask #1
0.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 43 ms 284 KB Not correct
2 Halted 0 ms 0 KB -

Subtask #2
0.0 / 85.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 444 ms 200 KB Not correct
2 Halted 0 ms 0 KB -