Submission #1121684

#	Time	Username	Problem	Language	Result	Execution time	Memory
1121684		aykhn	Calvinball championship (CEOI15_teams)	C++17	100 / 100	347 ms	16360 KiB

teams

#include <bits/stdc++.h>

using namespace std;

#define int long long
#define inf 0x3F3F3F3F

const int B = 1e2 + 5;
const int MXN = 1e4 + 5;
const int mod = 1e6 + 7;

int dp[B][MXN];
int bl[B][MXN];
int cur[MXN], nw[MXN];

signed main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n;
  cin >> n;
  int a[n + 1];
  for (int i = 1; i <= n; i++) cin >> a[i];
  for (int i = n; i >= 1; i--)
  {
    for (int j = 1; j <= n; j++) 
    {
      if (i == n) nw[j] = 1;
      else nw[j] = cur[j + 1] + (cur[j] * j) % mod;
    }
    for (int j = 1; j <= n; j++) cur[j] = nw[j];
    if (i % B == 0) for (int j = 1; j <= n; j++) bl[i / B][j] = cur[j];
  }
  if (B > n) for (int i = 1; i <= n; i++) dp[n % B][i] = 1;
  else for (int i = 1; i <= n; i++) dp[0][i] = bl[1][i];
  for (int i = min(B, n) - 1; i >= 1; i--) 
  {
    for (int j = 1; j <= n; j++)
    {
      dp[i % B][j] = (dp[(i + 1) % B][j + 1] + (dp[(i + 1) % B][j] * j)) % mod;
    }
  }
  int val = a[1], res = 0;
  for (int i = 1; i < n; i++)
  {
    val = max(val, a[i]);
    if (i % B == 0)
    {
      if ((i / B + 1) * B > n) for (int j = 1; j <= n; j++) dp[n % B][j] = 1;
      else for (int j = 1; j <= n; j++) dp[0][j] = bl[i / B + 1][j];
      for (int k = min((i / B + 1) * B, n) - 1; k > i; k--)
      {
        for (int j = 1; j <= n; j++)
        {
          dp[k % B][j] = (dp[(k + 1) % B][j + 1] + (dp[(k + 1) % B][j] * j)) % mod;
        }
      }
    }
    res = (res + (((a[i + 1] - 1) * dp[(i + 1) % B][val]) % mod));
  }
  cout << (res + 1) % mod << '\n';
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 10 / 10
• Subtask 4: 10 / 10
• Subtask 5: 10 / 10
• Subtask 6: 10 / 10
• Subtask 7: 10 / 10
• Subtask 8: 10 / 10
• Subtask 9: 10 / 10
• Subtask 10: 10 / 10