oj.uz

답안 #1094230

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
1094230 2024-09-29T04:53:44 Z vjudge1 Magneti (COCI21_magneti) C++14
0 / 110
 237 ms 524288 KB 
#include<bits/stdc++.h>
#define int long long
const int N=2e5+1;
const int mod=1e9+7;
int fac[N],ifac[N],a[N];
int f[52][52][30001];
int qmi(int x,int y){
	int res=1;
	while(y>0){
		if(y&1)
			res=res*x%mod;
		x=x*x%mod;
		y>>=1;
	}
	return res;
}
void init(int x){
	fac[0]=ifac[0]=1;
	for(int i=1;i<=x;i++)
		fac[i]=fac[i-1]*i%mod;
	ifac[x]=qmi(fac[x],mod-2);
	for(int i=x-1;i>=1;i--)
		ifac[i]=ifac[i+1]*(i+1)%mod;
}
inline int C(int n,int m){
	return (n<m||n<0||m<0)?0:fac[n]*ifac[m]%mod*ifac[n-m]%mod;
}
inline void add(int &x,int y){
	x+=y,x%=mod;
}
void solve(){
	int n,m;
	std::cin>>m>>n;
	for(int i=1;i<=m;i++)
		std::cin>>a[i];
	std::sort(a+1,a+m+1);
	memset(f,0,sizeof f);
	f[0][0][0]=1;
	for(int i=1;i<=m;i++){
		for(int j=1;j<=i;j++)
			for(int k=1;k<=n;k++){
				add(f[i][j][k],f[i-1][j-1][k-1]);
				if(k>=a[i])
					add(f[i][j][k],f[i-1][j][k-a[i]]*j*2%mod);
				if(k>=2*a[i]-1)
					add(f[i][j][k],f[i-1][j+1][k-2*a[i]+1]*j*(j+1)%mod);
			}
	}
	int ans=0;
	for(int i=1;i<=n;i++){
		ans=(ans+C(n-i+m,m)*f[m][1][i]%mod)%mod;
	}
	std::cout<<ans<<"\n";
}
signed main(){
	std::ios::sync_with_stdio(false),std::cin.tie(NULL),std::cout.tie(NULL);
	int t=1;
//	std::cin>>t;
	init(N-2);
	while(t--){
		solve();
	}
}

Subtask #1
0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 223 ms 524288 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #2
0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 225 ms 524288 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #3
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 237 ms 524288 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -

Subtask #4
0 / 50.0

# 결과 실행 시간 메모리 Grader output
1 Runtime error 223 ms 524288 KB Execution killed with signal 9
2 Halted 0 ms 0 KB -