oj.uz

Submission #856760

# Submission time Handle Problem Language Result Execution time Memory
856760 2023-10-04T13:02:38 Z raresmihai NoM (RMI21_nom) C++17
100 / 100
 130 ms 756 KB 
#include <iostream>

#define MOD 1000000007
#define MAXN 10000
using namespace std;

long long dp[MAXN + 1][2];
int val[MAXN];
long long fact[MAXN + 1];
long long invFact[MAXN + 1];
int m, n;

long long makeInv(long long x) {
  int pow;
  long long ans;

  ans = 1;
  pow = MOD - 2;
  while ( pow ) {
    if ( pow % 2 ) {
      ans = (ans * x) % MOD;
    }

    pow /= 2;
    x = (x * x) % MOD;
  }

  return ans;
}

void makeFact() {
  long long ans;
  int i;

  ans = 1;
  fact[0] = invFact[0] = 1;
  for ( i = 1; i <= MAXN; i++ ) {
    ans = (ans * i) % MOD;
    fact[i] = ans;
    invFact[i] = makeInv(ans);
  }
}

long long makeCombi(int n, int choose) {
  if ( n >= choose && choose >= 0 ) {
    return (((fact[n] * invFact[choose]) % MOD) * invFact[n - choose]) % MOD;
  }
  return 0;
}

long long makeChoose(int n, int choose) {
  if ( n >= choose && choose >= 0 ) {
    return (fact[n] * invFact[n - choose]) % MOD;
  }
  return 0;
}

long long calcAns(int a, int b, int x) { ///from a to b(x from b have pair); we choose from a increasing, other does not matter
  if ( a >= x && x >= 0 && b >= x ) {
    return (makeCombi(a, x) * makeChoose(b, x)) % MOD;
  }
  return 0;
}

void smh() {
  int currNr, i, pos, i2, i3;

  //makeFact();

  //scanf("%d%d", &n, &m);

  n *= 2;
  for ( i = 0; i < n; i++ ) {
    val[i % m]++;
  }

  pos = 0;
  dp[0][0] = 1;
  currNr = 0;
  for ( i = 0; i < m; i++ ) {
    pos ^= 1;

    for ( i2 = 0; i2 <= MAXN; i2++ ) {
      dp[i2][pos] = 0;
    }

    for ( i2 = 0; i2 <= val[i]; i2++ ) { //how many we pair
      for ( i3 = 0; i3 <= currNr; i3++ ) { //how many are used
        dp[i3 + 2 * i2][pos] = (dp[i3 + 2 * i2][pos] + (dp[i3][pos ^ 1] * calcAns(currNr - i3, val[i], i2)) % MOD) % MOD;
      }
    }

    currNr += val[i];
  }

  long long pow;

  pow = 1;
  for ( i = 1; i <= n / 2; i++ ) {
    pow = ((long long) pow * 2) % MOD;
  }

  printf("%lld\n", (((dp[n][pos] * fact[n / 2]) % MOD) * pow) % MOD);
}

int main() {
  makeFact();

  scanf("%d%d", &n, &m);

  smh();
}

Compilation message

Main.cpp: In function 'int main()':
Main.cpp:109:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
  109 |   scanf("%d%d", &n, &m);
      |   ~~~~~^~~~~~~~~~~~~~~~

Subtask #1
9.0 / 9.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 604 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 2 ms 604 KB Output is correct
5 Correct 2 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 2 ms 604 KB Output is correct
8 Correct 2 ms 604 KB Output is correct
9 Correct 2 ms 600 KB Output is correct
10 Correct 2 ms 604 KB Output is correct

Subtask #2
12.0 / 12.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 604 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 2 ms 604 KB Output is correct
5 Correct 2 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 2 ms 604 KB Output is correct
8 Correct 2 ms 604 KB Output is correct
9 Correct 2 ms 600 KB Output is correct
10 Correct 2 ms 604 KB Output is correct
11 Correct 2 ms 600 KB Output is correct
12 Correct 2 ms 604 KB Output is correct
13 Correct 2 ms 604 KB Output is correct
14 Correct 2 ms 604 KB Output is correct
15 Correct 2 ms 604 KB Output is correct
16 Correct 2 ms 604 KB Output is correct
17 Correct 2 ms 604 KB Output is correct
18 Correct 2 ms 604 KB Output is correct
19 Correct 2 ms 600 KB Output is correct

Subtask #3
13.0 / 13.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 604 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 2 ms 604 KB Output is correct
5 Correct 2 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 2 ms 604 KB Output is correct
8 Correct 2 ms 604 KB Output is correct
9 Correct 2 ms 600 KB Output is correct
10 Correct 2 ms 604 KB Output is correct
11 Correct 2 ms 600 KB Output is correct
12 Correct 2 ms 604 KB Output is correct
13 Correct 2 ms 604 KB Output is correct
14 Correct 2 ms 604 KB Output is correct
15 Correct 2 ms 604 KB Output is correct
16 Correct 2 ms 604 KB Output is correct
17 Correct 2 ms 604 KB Output is correct
18 Correct 2 ms 604 KB Output is correct
19 Correct 2 ms 600 KB Output is correct
20 Correct 2 ms 600 KB Output is correct
21 Correct 2 ms 604 KB Output is correct
22 Correct 5 ms 604 KB Output is correct
23 Correct 3 ms 604 KB Output is correct
24 Correct 4 ms 604 KB Output is correct
25 Correct 4 ms 604 KB Output is correct
26 Correct 3 ms 600 KB Output is correct
27 Correct 6 ms 604 KB Output is correct

Subtask #4
18.0 / 18.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 604 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 2 ms 604 KB Output is correct
5 Correct 2 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 2 ms 604 KB Output is correct
8 Correct 2 ms 604 KB Output is correct
9 Correct 2 ms 600 KB Output is correct
10 Correct 2 ms 604 KB Output is correct
11 Correct 2 ms 600 KB Output is correct
12 Correct 2 ms 604 KB Output is correct
13 Correct 2 ms 604 KB Output is correct
14 Correct 2 ms 604 KB Output is correct
15 Correct 2 ms 604 KB Output is correct
16 Correct 2 ms 604 KB Output is correct
17 Correct 2 ms 604 KB Output is correct
18 Correct 2 ms 604 KB Output is correct
19 Correct 2 ms 600 KB Output is correct
20 Correct 2 ms 600 KB Output is correct
21 Correct 2 ms 604 KB Output is correct
22 Correct 5 ms 604 KB Output is correct
23 Correct 3 ms 604 KB Output is correct
24 Correct 4 ms 604 KB Output is correct
25 Correct 4 ms 604 KB Output is correct
26 Correct 3 ms 600 KB Output is correct
27 Correct 6 ms 604 KB Output is correct
28 Correct 9 ms 604 KB Output is correct
29 Correct 13 ms 604 KB Output is correct
30 Correct 20 ms 756 KB Output is correct
31 Correct 9 ms 600 KB Output is correct
32 Correct 15 ms 604 KB Output is correct
33 Correct 19 ms 604 KB Output is correct
34 Correct 30 ms 592 KB Output is correct

Subtask #5
48.0 / 48.0

# Verdict Execution time Memory Grader output
1 Correct 2 ms 604 KB Output is correct
2 Correct 2 ms 604 KB Output is correct
3 Correct 2 ms 604 KB Output is correct
4 Correct 2 ms 604 KB Output is correct
5 Correct 2 ms 604 KB Output is correct
6 Correct 2 ms 600 KB Output is correct
7 Correct 2 ms 604 KB Output is correct
8 Correct 2 ms 604 KB Output is correct
9 Correct 2 ms 600 KB Output is correct
10 Correct 2 ms 604 KB Output is correct
11 Correct 2 ms 600 KB Output is correct
12 Correct 2 ms 604 KB Output is correct
13 Correct 2 ms 604 KB Output is correct
14 Correct 2 ms 604 KB Output is correct
15 Correct 2 ms 604 KB Output is correct
16 Correct 2 ms 604 KB Output is correct
17 Correct 2 ms 604 KB Output is correct
18 Correct 2 ms 604 KB Output is correct
19 Correct 2 ms 600 KB Output is correct
20 Correct 2 ms 600 KB Output is correct
21 Correct 2 ms 604 KB Output is correct
22 Correct 5 ms 604 KB Output is correct
23 Correct 3 ms 604 KB Output is correct
24 Correct 4 ms 604 KB Output is correct
25 Correct 4 ms 604 KB Output is correct
26 Correct 3 ms 600 KB Output is correct
27 Correct 6 ms 604 KB Output is correct
28 Correct 9 ms 604 KB Output is correct
29 Correct 13 ms 604 KB Output is correct
30 Correct 20 ms 756 KB Output is correct
31 Correct 9 ms 600 KB Output is correct
32 Correct 15 ms 604 KB Output is correct
33 Correct 19 ms 604 KB Output is correct
34 Correct 30 ms 592 KB Output is correct
35 Correct 54 ms 604 KB Output is correct
36 Correct 112 ms 736 KB Output is correct
37 Correct 49 ms 604 KB Output is correct
38 Correct 73 ms 604 KB Output is correct
39 Correct 81 ms 604 KB Output is correct
40 Correct 130 ms 744 KB Output is correct