#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define MAXN 100010
#define mod 998244353 
inline ll read(){
	ll x=0,f=1;
	char c=getchar();
	while(c<'0'||c>'9'){
		if(c=='-')f=-1;
		c=getchar();
	}
	while(c>='0'&&c<='9'){
		x=x*10+c-'0';
		c=getchar();
	}
	return x*f;
}
//ll fec[MAXN],infec[MAXN];
ll dp[MAXN][15],cnt[MAXN][15];
ll n,m,ans;
char c[MAXN];
int main(){
	freopen("sportk.in","r",stdin);
	freopen("sportk.out","w",stdout);
	n=read(),m=read();
	for(ll i=1;i<=n;i++){
		cin>>c[i];
		if(c[i]=='1')cnt[i][1]++,dp[i][1]++;
//		cout<<"id:"<<i<<" "<<c[i]<<" ";
		for(int j=1;j<=min(m,i);j++){
			cnt[i][j]=(cnt[i][j]+cnt[i-1][j-1]+cnt[i-1][j])%mod;
			dp[i][j]=(dp[i][j]+dp[i-1][j]+dp[i-1][j-1]*2+((c[i]=='1')?cnt[i-1][j-1]:0))%mod;
//			cout<<dp[i][j]<<" ";
		}
//		cout<<endl;
	}
	for(int i=1;i<=m;i++)ans=(ans+dp[n][i])%mod;
	cout<<ans;
	return 0;
}