oj.uz

Submission #127554

# Submission time Handle Problem Language Result Execution time Memory
127554 2019-07-09T14:50:52 Z RockyB Tents (JOI18_tents) C++17
100 / 100
 141 ms 35584 KB 
#include <bits/stdc++.h>
 
#define rep(a, b, c) for (int a = (b); (a) <= (c); a++)
#define per(a, b, c) for (int a = (b); (a) >= (c); a--)
 
#define nl '\n'
#define ioi exit(0);
 
const int mod = (int)1e9 + 7;
const int N = (int)1e4;
 
using namespace std;
 
void add(int &x, int y) {
  x += y;
  if (x >= mod) x -= mod;
}
int sum(int x, int y) {
  add(x, y);
  return x;
}
int n, m;
 
int dp[3005][3005];
int main() {
  #ifdef IOI
    freopen ("in.txt", "r", stdin);
    freopen ("slow.out", "w", stdout);
  #endif
  cin >> n >> m;
  /* memset(dp, -1, sizeof(dp));
  int ans = sum(calc(), -1);
  cout << ans << nl; */
  dp[0][m] = 1;
  rep(i, 0, n - 1) {
    rep(j, 0, m) {
      add(dp[i + 1][j], dp[i][j]);
      if (j > 0) {
        add(dp[i + 1][j - 1], dp[i][j] * 1ll * 4 * j % mod);
      	add(dp[i + 2][j - 1], dp[i][j] * 1ll * (n - i - 1) * j % mod);
      	
        if (j > 1) add(dp[i + 1][j - 2], dp[i][j] * 1ll * (j * (j - 1) / 2) % mod);
      }
    }
  }
  int ans = -1;
  rep(i, 0, m) add(ans, dp[n][i]);
  if (ans < 0) ans += mod;
  cout << ans;
  ioi
}
 
/*
 
5116 0
3720 1
450 2
 
*/

Subtask #1
48.0 / 48.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 504 KB Output is correct
4 Correct 3 ms 1144 KB Output is correct
5 Correct 3 ms 632 KB Output is correct
6 Correct 3 ms 1272 KB Output is correct
7 Correct 3 ms 760 KB Output is correct
8 Correct 3 ms 1400 KB Output is correct
9 Correct 2 ms 760 KB Output is correct
10 Correct 4 ms 1656 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 5 ms 1912 KB Output is correct

Subtask #2
52.0 / 52.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 376 KB Output is correct
2 Correct 2 ms 376 KB Output is correct
3 Correct 2 ms 504 KB Output is correct
4 Correct 3 ms 1144 KB Output is correct
5 Correct 3 ms 632 KB Output is correct
6 Correct 3 ms 1272 KB Output is correct
7 Correct 3 ms 760 KB Output is correct
8 Correct 3 ms 1400 KB Output is correct
9 Correct 2 ms 760 KB Output is correct
10 Correct 4 ms 1656 KB Output is correct
11 Correct 2 ms 376 KB Output is correct
12 Correct 5 ms 1912 KB Output is correct
13 Correct 2 ms 376 KB Output is correct
14 Correct 12 ms 9592 KB Output is correct
15 Correct 95 ms 32984 KB Output is correct
16 Correct 8 ms 2680 KB Output is correct
17 Correct 23 ms 8056 KB Output is correct
18 Correct 29 ms 11128 KB Output is correct
19 Correct 106 ms 34552 KB Output is correct
20 Correct 86 ms 29048 KB Output is correct
21 Correct 64 ms 19832 KB Output is correct
22 Correct 60 ms 22240 KB Output is correct
23 Correct 51 ms 19832 KB Output is correct
24 Correct 141 ms 35584 KB Output is correct
25 Correct 110 ms 30820 KB Output is correct
26 Correct 116 ms 33528 KB Output is correct
27 Correct 127 ms 34808 KB Output is correct