#include<cstdio>
#include<algorithm>
#define int long long
template<typename T>void read(T &x){
	x=0;bool f=0;char ch=getchar();
	for(;ch<'0'||ch>'9';ch=getchar())if(ch=='-')f=1;
	for(;ch>='0'&&ch<='9';ch=getchar())x=(x<<1)+(x<<3)+(ch^48);
	if(f)x=-x;
}
void write(char x){putchar(x);}
template<typename T>void write(T x){
	if(x<0)putchar('-'),x=-x;
	char stk[11];int cnt=0;
	do stk[++cnt]=x%10+48,x/=10;while(x);
	for(;cnt;)putchar(stk[cnt--]);
}
template<typename T,typename ...Args>void read(T &x,Args &...args){read(x);read(args...);}
template<typename T,typename ...Args>void write(T x,Args ...args){write(x);write(args...);}
template<typename T>T min(T x,T y){return x<y?x:y;}
template<typename T>T max(T x,T y){return x>y?x:y;}
const int mod=998244353;int n,m,a[10004],dp[104][10004],sum,fac[104],inv[104],ans;
int C(int n,int m){return fac[n]*inv[n-m]%mod*inv[m]%mod;}
int fast_pow(int x,int y){
	int res=1;
	for(;y;y>>=1,x=x*x%mod)if(y&1)res=res*x%mod;
	return res;
}
signed main(){
	read(n,m);dp[0][0]=1;
	for(int i=1;i<=n;++i)read(a[i]),sum+=a[i];
	for(int i=1;i<=n;++i)for(int j=n;j;--j)for(int k=sum;k>=a[i];--k)(dp[j][k]+=dp[j-1][k-a[i]])%=mod;
	inv[0]=fac[0]=1;
	for(int i=1;i<=n;++i)fac[i]=fac[i-1]*i%mod,inv[i]=fast_pow(fac[i],mod-2);
	for(int i=1;i<=n;++i)for(int j=1;j<=sum;++j){
		int tmp=fast_pow(C(n,i),mod-2);
		if(j>i*m)(ans+=tmp*m%mod*dp[i][j]%mod)%=mod;
		else (ans+=tmp*fast_pow(i,mod-2)%mod*j%mod*dp[i][j]%mod)%=mod;
	}
	write(ans);
	return 0;
}