oj.uz

Submission #218707

# Submission time Handle Problem Language Result Execution time Memory
218707 2020-04-02T14:37:32 Z eriksuenderhauf Ruins 3 (JOI20_ruins3) C++11
100 / 100
 325 ms 17272 KB 
//#pragma GCC optimize("O3")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define trav(x,a) for (const auto& x: a)
#define sz(x) (int)(x).size()
#define mem(a,v) memset((a), (v), sizeof (a))
#define enl printf("\n")
#define case(t) printf("Case #%d: ", (t))
#define ni(n) scanf("%d", &(n))
#define nl(n) scanf("%I64d", &(n))
#define nai(a, n) for (int _i = 1; _i <= (n); _i++) ni(a[_i])
#define nal(a, n) for (int _i = 1; _i <= (n); _i++) nl(a[_i])
#define pri(n) printf("%d\n", (n))
#define prl(n) printf("%I64d\n", (n))
#define pii pair<int, int>
#define pll pair<long long, long long>
#define vii vector<pii>
#define vll vector<pll>
#define vi vector<int>
#define vl vector<long long>
#define pb push_back
#define mp make_pair
#define st first
#define nd second
using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef cc_hash_table<int,int,hash<int>> ht;
typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> oset;
const double pi = acos(-1);
const int mod = 1e9 + 7;
const int inf = 1e9 + 7;
const int N = 2e3 + 5;
const double eps = 1e-9;
int a[N], C[N][N], fac[N], dp[N][N];

int add(int x, int y) { return x+y < mod ? x+y : x+y-mod; }
int mul(int x, int y) { return x*1ll*y % mod; }

int main() {
  fac[0] = C[0][0] = 1;
  for (int i = 1; i < N; i++) {
    fac[i] = mul(fac[i-1], i);
    C[i][0] = 1;
    for (int j = 1; j <= i; j++)
      C[i][j] = add(C[i-1][j], C[i-1][j-1]);
  }
  int n; ni(n);
  for (int i = 1; i <= n; i++) {
    scanf("%d", a+i);
  }
  dp[1][1] = 1;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= n+1; j++) {
      if (dp[i][j] == 0)
        continue;
      for (int k = 0; k <= min(n, a[i] - i) - j + 1; k++) {
        int val = mul(mul(dp[i][j], C[2*k][k]), mul(C[a[i]-i-j+1][k], fac[k]));
        dp[i+1][j+k] = add(dp[i+1][j+k], mul(val, k > 0 ? 1 : j - i));
      }
    }
  }
  int ans = dp[n+1][n+1];
  for (int i = 1; i <= n; i++)
    ans = mul(ans, 500000004);
  printf("%d\n", ans);
  return 0;
}

Compilation message

ruins3.cpp: In function 'int main()':
ruins3.cpp:10:20: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
 #define ni(n) scanf("%d", &(n))
               ~~~~~^~~~~~~~~~~~
ruins3.cpp:49:10: note: in expansion of macro 'ni'
   int n; ni(n);
          ^~
ruins3.cpp:51:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d", a+i);
     ~~~~~^~~~~~~~~~~

Subtask #1
6.0 / 6.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 14208 KB Output is correct
2 Correct 13 ms 14080 KB Output is correct
3 Correct 13 ms 14208 KB Output is correct
4 Correct 14 ms 14208 KB Output is correct
5 Correct 13 ms 14208 KB Output is correct
6 Correct 14 ms 14208 KB Output is correct
7 Correct 13 ms 14208 KB Output is correct
8 Correct 15 ms 14208 KB Output is correct
9 Correct 14 ms 14208 KB Output is correct
10 Correct 13 ms 14208 KB Output is correct

Subtask #2
52.0 / 52.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 14208 KB Output is correct
2 Correct 13 ms 14080 KB Output is correct
3 Correct 13 ms 14208 KB Output is correct
4 Correct 14 ms 14208 KB Output is correct
5 Correct 13 ms 14208 KB Output is correct
6 Correct 14 ms 14208 KB Output is correct
7 Correct 13 ms 14208 KB Output is correct
8 Correct 15 ms 14208 KB Output is correct
9 Correct 14 ms 14208 KB Output is correct
10 Correct 13 ms 14208 KB Output is correct
11 Correct 13 ms 14464 KB Output is correct
12 Correct 14 ms 14464 KB Output is correct
13 Correct 17 ms 14592 KB Output is correct
14 Correct 13 ms 14464 KB Output is correct
15 Correct 13 ms 14208 KB Output is correct
16 Correct 15 ms 14464 KB Output is correct
17 Correct 13 ms 14208 KB Output is correct
18 Correct 13 ms 14464 KB Output is correct
19 Correct 14 ms 14464 KB Output is correct
20 Correct 14 ms 14464 KB Output is correct

Subtask #3
42.0 / 42.0

# Verdict Execution time Memory Grader output
1 Correct 14 ms 14208 KB Output is correct
2 Correct 13 ms 14080 KB Output is correct
3 Correct 13 ms 14208 KB Output is correct
4 Correct 14 ms 14208 KB Output is correct
5 Correct 13 ms 14208 KB Output is correct
6 Correct 14 ms 14208 KB Output is correct
7 Correct 13 ms 14208 KB Output is correct
8 Correct 15 ms 14208 KB Output is correct
9 Correct 14 ms 14208 KB Output is correct
10 Correct 13 ms 14208 KB Output is correct
11 Correct 13 ms 14464 KB Output is correct
12 Correct 14 ms 14464 KB Output is correct
13 Correct 17 ms 14592 KB Output is correct
14 Correct 13 ms 14464 KB Output is correct
15 Correct 13 ms 14208 KB Output is correct
16 Correct 15 ms 14464 KB Output is correct
17 Correct 13 ms 14208 KB Output is correct
18 Correct 13 ms 14464 KB Output is correct
19 Correct 14 ms 14464 KB Output is correct
20 Correct 14 ms 14464 KB Output is correct
21 Correct 17 ms 16640 KB Output is correct
22 Correct 16 ms 16640 KB Output is correct
23 Correct 16 ms 16640 KB Output is correct
24 Correct 18 ms 16640 KB Output is correct
25 Correct 15 ms 14208 KB Output is correct
26 Correct 14 ms 14208 KB Output is correct
27 Correct 14 ms 14208 KB Output is correct
28 Correct 15 ms 16640 KB Output is correct
29 Correct 14 ms 14208 KB Output is correct
30 Correct 321 ms 17272 KB Output is correct
31 Correct 164 ms 17144 KB Output is correct
32 Correct 239 ms 17272 KB Output is correct
33 Correct 325 ms 17272 KB Output is correct
34 Correct 162 ms 17144 KB Output is correct
35 Correct 241 ms 17272 KB Output is correct
36 Correct 305 ms 17272 KB Output is correct