#include<iostream>
#include<cstdio>
#include<cstring>
#include<algorithm>
using namespace std; 
char ffind[3010];
char str[3000001];
char c[3010];
int i,j;
int m,n;
int main()
{
    freopen("writing.in","r",stdin);
    freopen("writing.out","w",stdout);
    cin>>m>>n;
    cin>>ffind>>str;
    int cnt=0;
    sort(ffind,ffind+m);
    for(i=0;i<n;i++){
    	for(j=0;j<m;j++){
    		c[j]=str[i+j];
    	}
    	c[m]=0;
    	sort(c,c+m);
    	if(!strcmp(c,ffind))
    	{
    		cnt++;
    	}
    }
    cout<<cnt<<endl;
}