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Submission #1094043

# Submission time Handle Problem Language Result Execution time Memory
1094043 2024-09-28T11:00:04 Z vjudge1 Magneti (COCI21_magneti) C++17
0 / 110
 45 ms 25692 KB 
#include<bits/stdc++.h>
#define int long long
const int N=2e5+1;
int mod=1e9+7;
int fac[N],ifac[N],a[N];
int f[61][61][15100];
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>>n>>m;
	for(int i=0;i<m;i++)
		std::cin>>a[i];
	std::sort(a,a+m);
	f[0][0][0]=1;
	for(int i=0;i<m;i++){
		for(int j=0;j<=i;j++)
			for(int k=0;k<=n;k++){
				add(f[i+1][j+1][k+1],f[i][j][k]*(j+1)%mod);
				if(k+a[i]<=n)
					add(f[i+1][j][k+a[i]],f[i][j][k]*j*2%mod);
				if(k+2*a[i]-1<=n&&k+2*a[i]-1>=0)
					add(f[i+1][j-1][k+2*a[i]-1],f[i][j][k]*(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-1);
	while(t--){
		solve();
	}
}

Subtask #1
0 / 10.0

# Verdict Execution time Memory Grader output
1 Runtime error 35 ms 25692 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Runtime error 34 ms 24404 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #3
0 / 30.0

# Verdict Execution time Memory Grader output
1 Runtime error 45 ms 24916 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -

Subtask #4
0 / 50.0

# Verdict Execution time Memory Grader output
1 Runtime error 35 ms 25692 KB Execution killed with signal 11
2 Halted 0 ms 0 KB -