Submission #703021

#	Time	Username	Problem	Language	Result	Execution time	Memory
703021		406	Swap (BOI16_swap)	C++17	0 / 100	6 ms	9684 KiB

swap

#include "bits/stdc++.h"
using namespace std;
#define int long long
const int N = 2e5 + 5;
const int L = 20;
const long long INF = 1ll << 60;
map<int, vector<int>> dp[N];
int n, a[4 * N];

void merge(vector<int> &a, const vector<int> b, const vector<int> c) {
    assert(b.size() && c.size());
    assert(b.size() == c.size());
    int ptr = 0;
    for (int i = 0; ptr < b.size(); i++) {
        for (int j = 0; j < (1 << i); j++) {
            a.push_back(b[j + ptr]);
        }
        for (int j = 0; j < (1 << i); j++) {
            a.push_back(c[j + ptr]);
        }
        ptr += 1 << i;
    }
}   

void DP(int i, int j) {
    if (i >= n / 2) {
        dp[i][j] = {j};
        return;
    }
    int r = a[2 * i + 1];
    int l = a[2 * i];
    if (j <= l && j <= r) {
        DP(i * 2, l);
        DP(i * 2 + 1, r);
        vector<int> re{j};
        merge(re, dp[i << 1][l], dp[i << 1 | 1][r]);
        dp[i][j] = re;
        return;
    }
    
    if (j <= a[2 * i]) {
        DP(i * 2, j);
        DP(i * 2 + 1, j);
        DP(i * 2, l);
        DP(i * 2 + 1, l);
        vector<int> re{r};
        merge(re, dp[i * 2][l], dp[i * 2 + 1][j]);

        vector<int> re2{r};
        merge(re2, dp[i * 2][j], dp[i * 2 + 1][l]);

        dp[i][j] = min(re, re2);
        return;
    }
    if (j <= a[2 * i + 1]) {
        DP(i * 2, j);
        DP(i * 2 + 1, r);
        vector<int> re{j};
        merge(re, dp[i << 1][j], dp[i << 1 | 1][r]);
        dp[i][j] = re;
        return;
    }
    DP(i * 2, j);
    DP(i * 2 + 1, j);
    DP(i * 2, r);
    DP(i * 2 + 1, r);
    DP(i * 2, l);
    DP(i * 2 + 1, l);

    vector<int> re{r};
    merge(re, dp[i * 2][l], dp[i * 2 + 1][j]);

    vector<int> re2{r};
    merge(re2, dp[i * 2][j], dp[i * 2 + 1][l]);

    vector<int> re3{l}; 
    merge(re3, dp[i * 2][r], dp[i * 2 + 1][j]);

    vector<int> re4{l}; 
    merge(re4, dp[i * 2][j], dp[i * 2 + 1][r]);

    re = min(re, re2);
    re = min(re, re3);
    re = min(re, re4);
    dp[i][j] = re;
}

signed main() {
    ios::sync_with_stdio(0);
    cin.tie(0);

    cin >> n;
    for (int i = 1; i <= n; i++) 
        cin >> a[i];

    while (n & (n - 1)) {
        a[++n] = INF;
    }

    DP(1, a[1]);
    for (auto u: dp[1][a[1]]) if (u != INF)
        cout << u << ' ';
    cout << '\n';

    return 0;
}

Compilation message (stderr)

swap.cpp: In function 'void merge(std::vector<long long int>&, std::vector<long long int>, std::vector<long long int>)':
swap.cpp:14:25: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   14 |     for (int i = 0; ptr < b.size(); i++) {
      |                     ~~~~^~~~~~~~~~

• Subtask 1: 0 / 10
• Subtask 2: 0 / 11
• Subtask 3: 0 / 27
• Subtask 4: 0 / 20
• Subtask 5: 0 / 32