#include <cstdio>

 #include <cstring>

 #include <iostream>

 #include <algorithm>

 #include <cmath>

 #include <string>

 #include <vector>

 #include <queue>

 #include <set>

 using namespace std;

 #define ll long long

 #define inf 0x3f3f3f3f

 #define eps 1e-8

 #define maxn 100010

 int a[maxn],b[maxn];

 int dp[];

 vector<int>x[maxn];

 int main(){

     int n,m,s,e;

     while(~scanf("%d%d%d%d",&n,&m,&s,&e)){

         memset(dp,0x3f,sizeof(dp));

         dp[]=;

         for(int i=;i<n;++i)scanf("%d",a+i);

         //for(int i=0;i<maxn;++i)x[i].clear();

         for(int i=;i<m;++i)scanf("%d",b+i),x[b[i]].push_back(i+);

         int ans=;

         for(int i=;i<n;++i){

             for(int j=s/e;j>=;--j){

                 vector<int>::iterator it=upper_bound(x[a[i]].begin(),x[a[i]].end(),dp[j]);

                 if(it==x[a[i]].end())continue;

                 dp[j+]=min(*it,dp[j+]);

                 if(i++dp[j+]+(j+)*e<=s)

                     ans = max(ans,j+);

             }

         }

         printf("%d\n",ans);

     }

     return ;

 }