답안 #921454

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
921454 2024-02-03T21:58:55 Z _Morningstar 캥거루 (CEOI16_kangaroo) C++14
100 / 100
16 ms 16192 KB
#include<bits/stdc++.h>

using namespace std;

#define ll long long
#define fr(m) for(int i=0; i<m; i++)
#define fro(m) for(int i=1; i<m; i++)
#define frj(m) for(int j=0; j<m; j++)
#define frr(n) for(int i=n; i>=0; i--)
#define pb push_back
#define pf push_front
#define orr ||
#define nl '\n'
#define nll cout<<'\n'
#define mod 1000000007
#define inf (1LL<<61)
#define inff (1<<30)
#define yes cout<<"YES"<<nl
#define no cout<<"NO"<<nl
#define ff first
#define ss second
#define all(v) v.begin(), v.end()
#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define mxn 2005

template<int MOD>
struct ModInt {
  unsigned x;
  ModInt() : x(0) { }
  ModInt(signed sig) : x((sig>=MOD)?sig%MOD:sig) { }
  ModInt(signed long long sig) : x(sig%MOD) { }
  int get() const { return (int)x; }
  ModInt pow(ll p) { ModInt res = 1, a = *this; while (p) { if (p & 1) res *= a; a *= a; p >>= 1; } return res; }
 
  ModInt &operator+=(ModInt that) { if ((x += that.x) >= MOD) x -= MOD; return *this; }
  ModInt &operator-=(ModInt that) { if ((x += MOD - that.x) >= MOD) x -= MOD; return *this; }
  ModInt &operator*=(ModInt that) { x = (unsigned long long)x * that.x % MOD; return *this; }
  ModInt &operator/=(ModInt that) { return (*this) *= that.pow(MOD - 2); }
 
  ModInt operator+(ModInt that) const { return ModInt(*this) += that; }
  ModInt operator-(ModInt that) const { return ModInt(*this) -= that; }
  ModInt operator*(ModInt that) const { return ModInt(*this) *= that; }
  ModInt operator/(ModInt that) const { return ModInt(*this) /= that; }
  bool operator<(ModInt that) const { return x < that.x; }
  friend ostream& operator<<(ostream &os, ModInt a) { os << a.x; return os; }
  friend istream& operator>>(istream &is, ModInt &a) { is >> a.x; return is; }
};
typedef ModInt<mod> mint;//change mod here


ll n, a, b;
mint dp[mxn][mxn];

int main()
{
    fastio;
    cin>>n>>a>>b;
    dp[1][1]=1;
    for(int i=2; i<=n; i++){
        for(int j=1; j<=n; j++){
            if(i==a || i==b) dp[i][j]=dp[i-1][j]+dp[i-1][j-1];
            else{
                //merge
                dp[i][j]+=dp[i-1][j+1]*j;
                //new comp
                dp[i][j]+=dp[i-1][j-1]*max(0,j-(i>a)-(i>b));
            }
        }
    }
    cout<<dp[n][1]<<nl;
    return 0;
}
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 15964 KB Output is correct
2 Correct 3 ms 15996 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 15964 KB Output is correct
2 Correct 3 ms 15996 KB Output is correct
3 Correct 3 ms 15960 KB Output is correct
4 Correct 3 ms 16188 KB Output is correct
5 Correct 4 ms 15964 KB Output is correct
6 Correct 3 ms 16188 KB Output is correct
7 Correct 3 ms 15964 KB Output is correct
8 Correct 3 ms 15964 KB Output is correct
9 Correct 3 ms 15964 KB Output is correct
10 Correct 3 ms 15964 KB Output is correct
11 Correct 3 ms 15964 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 15964 KB Output is correct
2 Correct 3 ms 15996 KB Output is correct
3 Correct 3 ms 15960 KB Output is correct
4 Correct 3 ms 16188 KB Output is correct
5 Correct 4 ms 15964 KB Output is correct
6 Correct 3 ms 16188 KB Output is correct
7 Correct 3 ms 15964 KB Output is correct
8 Correct 3 ms 15964 KB Output is correct
9 Correct 3 ms 15964 KB Output is correct
10 Correct 3 ms 15964 KB Output is correct
11 Correct 3 ms 15964 KB Output is correct
12 Correct 3 ms 15964 KB Output is correct
13 Correct 3 ms 16188 KB Output is correct
14 Correct 3 ms 15964 KB Output is correct
15 Correct 3 ms 15964 KB Output is correct
16 Correct 3 ms 15960 KB Output is correct
17 Correct 3 ms 15964 KB Output is correct
18 Correct 3 ms 15964 KB Output is correct
19 Correct 4 ms 15964 KB Output is correct
20 Correct 3 ms 15960 KB Output is correct
# 결과 실행 시간 메모리 Grader output
1 Correct 3 ms 15964 KB Output is correct
2 Correct 3 ms 15996 KB Output is correct
3 Correct 3 ms 15960 KB Output is correct
4 Correct 3 ms 16188 KB Output is correct
5 Correct 4 ms 15964 KB Output is correct
6 Correct 3 ms 16188 KB Output is correct
7 Correct 3 ms 15964 KB Output is correct
8 Correct 3 ms 15964 KB Output is correct
9 Correct 3 ms 15964 KB Output is correct
10 Correct 3 ms 15964 KB Output is correct
11 Correct 3 ms 15964 KB Output is correct
12 Correct 3 ms 15964 KB Output is correct
13 Correct 3 ms 16188 KB Output is correct
14 Correct 3 ms 15964 KB Output is correct
15 Correct 3 ms 15964 KB Output is correct
16 Correct 3 ms 15960 KB Output is correct
17 Correct 3 ms 15964 KB Output is correct
18 Correct 3 ms 15964 KB Output is correct
19 Correct 4 ms 15964 KB Output is correct
20 Correct 3 ms 15960 KB Output is correct
21 Correct 4 ms 15960 KB Output is correct
22 Correct 5 ms 15964 KB Output is correct
23 Correct 5 ms 15980 KB Output is correct
24 Correct 15 ms 15964 KB Output is correct
25 Correct 15 ms 15960 KB Output is correct
26 Correct 16 ms 15964 KB Output is correct
27 Correct 15 ms 15964 KB Output is correct
28 Correct 10 ms 16192 KB Output is correct