#include <bits/stdc++.h>
using namespace std;
typedef signed long long ll;

#define _P(...) (void)printf(__VA_ARGS__)
#define FOR(x,to) for(x=0;x<(to);x++)
#define FORR(x,arr) for(auto& x:arr)
#define FORR2(x,y,arr) for(auto& [x,y]:arr)
#define ALL(a) (a.begin()),(a.end())
#define ZERO(a) memset(a,0,sizeof(a))
#define MINUS(a) memset(a,0xff,sizeof(a))
template<class T> bool chmax(T &a, const T &b) { if(a<b){a=b;return 1;}return 0;}
template<class T> bool chmin(T &a, const T &b) { if(a>b){a=b;return 1;}return 0;}
//-------------------------------------------------------

int N,M,K;
string S,T,SA,SB,TA,TB;
using VT = string;

bitset<512000> SC,TC,mask;

vector<int> Zalgo(VT s) {
	vector<int> v(1,s.size());
	for(int i=1,l=-1,r=-1;i<s.size();i++) {
		if(i<=r && v[i-l]<r-i+1) v.push_back(v[i-l]);
		else {
			l=i; r=(i>r)?i:(r+1);
			while(r<s.size() && s[r-i]==s[r]) r++;
			v.push_back((r--)-l);
		}
	}
	v.push_back(0);
	return v;
}

void solve() {
	int i,j,k,l,r,x,y; string s;
	
	cin>>N>>M>>K>>S>>T;
	FORR(c,S) {
		if(c>='a'&&c<='z') {
			SA+=c;
			SB+="a";
		}
		else {
			SA+=c-'A'+'a';
			SB+="A";
		}
	}
	FORR(c,T) {
		if(c>='a'&&c<='z') {
			TA+=c;
			TB+="a";
		}
		else {
			TA+=c-'A'+'a';
			TB+="A";
		}
	}
	
	TA+="*"+SA;
	T+="*"+S;
	FOR(i,N) SC[i]=SB[i]=='a';
	FOR(i,M) {
		TC[i]=TB[i]=='a';
		mask[i]=1;
	}
	
	
	auto ZA=Zalgo(TA);
	auto Z=Zalgo(T);
	int ret=0;
	FOR(i,N-M+1) if(Z[i+1+M]<M&&ZA[i+1+M]==M) {
		auto TT=TC;
		TT^=SC>>i;
		TT&=mask;
		if(TT.count()<=K) ret++;
	}
	cout<<ret<<endl;
	
	
}


int main(int argc,char** argv){
	string s;int i;
	if(argc==1) ios::sync_with_stdio(false), cin.tie(0);
	FOR(i,argc-1) s+=argv[i+1],s+='\n'; FOR(i,s.size()) ungetc(s[s.size()-1-i],stdin);
	cout.tie(0); solve(); return 0;
}