Submission #755933

#	Time	Username	Problem	Language	Result	Execution time	Memory
755933		vjudge1	A Huge Tower (CEOI10_tower)	C++17	45 / 100	1082 ms	208416 KiB

tower

#include <bits/stdc++.h>

using namespace std;

#ifdef LOCAL
#include "C:\GCC\debug.h"
#else
#define debug(...) void(42)
#endif

const int md = 1000000009;
const int MaxN = 1 << 20;

int add(int &a, int b) {
  a += b;
  if (a > md) {
    a -= md;
  }
  return a;
}

int dp[MaxN + 1][25];

int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, d;
  cin >> n >> d;
  vector<int> a(n);
  for (int i = 0; i < n; i++) {
    cin >> a[i];
  }
  for (int i = 0; i < (1 << n); i++) {
    for (int j = 0; j <= n; j++) {
      dp[i][j] = -1;
    }
  }

  function<int(int, int)> DP = [&](int mask, int prev) {
    if (mask == (1 << n) - 1) {
      return 1;
    }
    if (dp[mask][prev + 1] != -1) {
      return dp[mask][prev + 1];
    }
    int ways = 0;
    for (int j = 0; j < n; j++) {
      if ((1 << j) & mask || (prev > -1 && a[j] - d > a[prev])) {
        continue;
      }
      add(ways, DP(mask | (1 << j), j));
    }
    return dp[mask][prev + 1] = ways;
  };

  cout << DP(0, -1) << '\n';
  return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 5 / 5
• Subtask 4: 5 / 5
• Subtask 5: 5 / 5
• Subtask 6: 5 / 5
• Subtask 7: 5 / 5
• Subtask 8: 5 / 5
• Subtask 9: 5 / 5
• Subtask 10: 0 / 5
• Subtask 11: 0 / 5
• Subtask 12: 0 / 5
• Subtask 13: 0 / 5
• Subtask 14: 0 / 5
• Subtask 15: 0 / 5
• Subtask 16: 0 / 5
• Subtask 17: 0 / 5
• Subtask 18: 0 / 5
• Subtask 19: 0 / 5
• Subtask 20: 0 / 5