//g++ 2.cpp -std=c++14 -O2 -I .
#include <bits/stdc++.h>
using namespace std;

#include <atcoder/all>
using namespace atcoder;

using ll = long long;
using ld = long double;

using vi = vector<int>;
using vvi = vector<vi>;
using vll = vector<ll>;
using vvll = vector<vll>;
using vld = vector<ld>;
using vvld = vector<vld>;

#define fi first
#define se second
#define pb push_back
#define pq_big(T) priority_queue<T,vector<T>,less<T>>
#define pq_small(T) priority_queue<T,vector<T>,greater<T>>
#define all(a) a.begin(),a.end()
#define rep(i,start,end) for(ll i=start;i<(ll)(end);i++)
#define per(i,start,end) for(ll i=start;i>=(ll)(end);i--)
#define uniq(a) sort(all(a));a.erase(unique(all(a)),a.end())

const int MAX=510000;
const long long MOD=998244353;

long long fac[MAX],finv[MAX],inv[MAX],pow2[MAX];

void COMinit(){
  fac[0]=fac[1]=1;
  finv[0]=finv[1]=1;
  inv[1]=1;
  for(int i=2;i<MAX;i++){
    fac[i]=fac[i-1]*i%MOD;
    inv[i]=MOD-inv[MOD%i]*(MOD/i)%MOD;
    finv[i]=finv[i-1]*inv[i]%MOD;
  }
}

long long COM(int n,int k){
  if(n<k) return 0;
  if(n<0||k<0) return 0;
  return fac[n]*(finv[k]*finv[n-k]%MOD)%MOD;
}

constexpr ll mod = 998244353;

map<pair<int,int>,int> seen;
map<pair<int,int>,ll> value;

ll solve(int n,int m,int k,string x){
  if(x==""){
    return 1;
  }
  if(seen[{n,m}]==true){
    return value[{n,m}];
  }

  string next=x.substr(1);
  ll res=0;

  if(x[0]=='0'){
    //0 k個以上必要
    rep(i,k,n+1){
      //0をi個置く場合
      ll com=COM(n,i);
      com*=pow_mod(pow2[m-1],n-i,mod);
      com%=mod;
      com*=solve(i,m-1,k,next);
      res=(res+com)%mod;
    }
  }
  else{
    //0 k個未満必要
    rep(i,0,k){
      //0をi個置く場合
      ll com=COM(n,i);
      com*=solve(n,m-1,k,next);
      res=(res+com)%mod;
    }
  }

  seen[{n,m}]=true;
  value[{n,m}]=res;
  return res;
}

int main(){
  ios::sync_with_stdio(false);
  cin.tie(nullptr);

  COMinit();

  pow2[0]=1;
  rep(i,1,MAX){
    pow2[i]=pow2[i-1]*2;
    pow2[i]%=mod;
  }

  int n,m,k;
  cin>>n>>m>>k;
  string x;
  cin>>x;

  cout<<solve(n,m,k,x)<<endl;
}