#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define fi first
#define in inline
#define se second
#define mp make_pair
#define pb push_back
const int N = 1e5+10;
const ll mod = 998244353;

ll read(){
	ll x = 0,f = 1;char c = getchar();
	for(;c < '0' || c > '9';c = getchar())if(c == '-')f = -1;
	for(;c >= '0' && c <= '9';c = getchar())x = (x<<1) + (x<<3) + c-'0';
	return x * f;
}


int n,m;
char c[N];
ll f[N][12],s[N][12];
int main(){
	freopen("sportk.in","r",stdin);
	freopen("sportk.out","w",stdout);
	n = read(),m = read();
	scanf("%s",c + 1);
	for(int i = 1;i <= n;i++)f[i][1] = f[i-1][1] + (c[i] == '1'),s[i][1] = f[i][1];
	for(int i = 1;i <= n;i++){
		for(int j = 2;j <= m;j++){
			s[i][j] = (s[i-1][j] + s[i-1][j-1]) % mod;
			f[i][j] = (f[i-1][j] + f[i-1][j-1] * 2 % mod + s[i-1][j-1] * (c[i] == '1')) % mod;
		}
	}
	ll ans = 0;
	for(int i = 1;i <= m;i++)(ans += f[n][i]) %= mod;
	printf("%lld\n",ans);

	return 0;

}