Submission #771414

#	Time	Username	Problem	Language	Result	Execution time	Memory
771414		PurpleCrayon	Prisoner Challenge (IOI22_prison)	C++17	56 / 100	11 ms	1136 KiB

prison

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

#define sz(v) int(v.size())

const int B = 12;
vector<vector<int>> devise_strategy(int n) {
    vector<vector<int>> ans(2 * (B + 1) + 1, vector<int>(n + 1));
    for (int i = 0; i < sz(ans); i++) {
        if (i == 0) {
            ans[i][0] = 0;
            int b = 0;
            for (int j = 1; j <= n; j++) {
                if ((j >> (B - b)) & 1) {
                    ans[i][j] = 2;
                } else {
                    ans[i][j] = 1;
                }
            }
        } else {
            int b = (i - 1) / 2;
            int last = (i - 1) % 2;
            if (b % 2 == 0) {
                ans[i][0] = 1;
            } else {
                ans[i][0] = 0;
            }

            for (int j = 1; j <= n; j++) {
                int cur = (j >> (B - b)) & 1;
                if (cur != last) {
                    if (cur < last) ans[i][j] = -ans[i][0] - 1;
                    else ans[i][j] = -(ans[i][0] ^ 1) - 1;
                } else {
                    if (B == b) { // unreachable state
                        ans[i][j] = -1;
                        continue;
                    }

                    if ((j >> (B - b - 1)) & 1) {
                        ans[i][j] = 2 * (b + 1) + 2;
                    } else {
                        ans[i][j] = 2 * (b + 1) + 1;
                    }
                }
            }
        }
    }

    return ans;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 46 / 90