oj.uz

Submission #501311

# Submission time Handle Problem Language Result Execution time Memory
501311 2022-01-02T19:11:40 Z inksamurai Zapina (COCI20_zapina) C++17
55 / 110
 1000 ms 344 KB 
#include <bits/stdc++.h>
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(),a.end()
#define rep(i,n) for(int i=0;i<n;i++)
#define crep(i,x,n) for(int i=x;i<n;i++)
#define drep(i,n) for(int i=n-1;i>=0;i--)
#define vec(...) vector<__VA_ARGS__>
#define _3qplfh5 ios_base::sync_with_stdio(false),cin.tie(0),cout.tie(0)
using namespace std;
typedef long long ll;
typedef long double ld;
using pii=pair<int,int>;
using vi=vector<int>;
using vll=vector<long long>;

//snuke's mod int
template <ll mod>
struct modint{
  ll x; // typedef long long ll;
  modint(ll x=0):x((x%mod+mod)%mod){}
  modint operator-()const{ return modint(-x);}
  modint& operator+=(const modint a){ if((x+=a.x)>=mod) x-=mod; return *this; }
  modint& operator-=(const modint a){ if((x+=mod-a.x)>=mod) x-=mod; return *this; }
  modint& operator*=(const modint a){ (x*=a.x)%=mod; return *this; }
  modint operator+(const modint a)const{ modint res(*this); return res+=a; }
  modint operator-(const modint a)const{ modint res(*this); return res-=a; }
  modint operator*(const modint a)const{ modint res(*this); return res*=a; }
  modint pow(ll n) const {
    modint res=1,x(*this);
    while(n){
        if(n&1)res*=x;
        x*=x;
        n>>=1;
    }
    return res;
  }
  modint inv() const { return pow(mod-2); }
};
using mint=modint<1000000007>;

const int mxn=400;
mint fact[mxn+10];
void prefact(){
fact[0]=fact[1]=1;
  crep(i,2,mxn){
    mint x=i;
    fact[i]=fact[i-1]*x;
  }
}

mint cnk(ll k,ll n){
  if(k>n) return 0;
  mint e=fact[k]*fact[n-k];
  return fact[n] * e.inv();
}

int main(){
_3qplfh5;
prefact();
	int n;
	cin>>n;
	vec(vec(mint)) dp(n+1,vec(mint)(2)),nedp;
	dp[0][0]=1;
	rep(i,n){
		int need=i+1;
		nedp=vec(vec(mint))(n+1,vec(mint)(2));
		rep(j,n+1){
			rep(k,(n-j)+1){
				rep(t,2){
					int net=t;
					if(k==need) net=1;
					nedp[j+k][net]+=dp[j][t]*cnk(k,n-j);
				}
			}
		}
		swap(dp,nedp);
		// cout<<dp[1][1].x<<"\n";
	}
	cout<<dp[n][1].x<<"\n";
//	
	return 0;
}

Subtask #1
22.0 / 22.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 316 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 320 KB Output is correct
4 Correct 1 ms 316 KB Output is correct
5 Correct 1 ms 204 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 316 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 320 KB Output is correct
4 Correct 1 ms 316 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 204 KB Output is correct
12 Correct 1 ms 204 KB Output is correct
13 Correct 1 ms 204 KB Output is correct
14 Correct 2 ms 204 KB Output is correct
15 Correct 2 ms 204 KB Output is correct
16 Correct 2 ms 204 KB Output is correct

Subtask #3
0 / 55.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 316 KB Output is correct
2 Correct 0 ms 204 KB Output is correct
3 Correct 0 ms 320 KB Output is correct
4 Correct 1 ms 316 KB Output is correct
5 Correct 1 ms 204 KB Output is correct
6 Correct 1 ms 204 KB Output is correct
7 Correct 1 ms 204 KB Output is correct
8 Correct 1 ms 204 KB Output is correct
9 Correct 1 ms 204 KB Output is correct
10 Correct 1 ms 204 KB Output is correct
11 Correct 1 ms 204 KB Output is correct
12 Correct 1 ms 204 KB Output is correct
13 Correct 1 ms 204 KB Output is correct
14 Correct 2 ms 204 KB Output is correct
15 Correct 2 ms 204 KB Output is correct
16 Correct 2 ms 204 KB Output is correct
17 Execution timed out 1097 ms 344 KB Time limit exceeded
18 Halted 0 ms 0 KB -