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


int main(){
    ios_base::sync_with_stdio(false);cin.tie(nullptr);
    int m,k,n,s;
    cin>>m>>k>>n>>s;
    int a[m];
    for(int i=0;i<m;i++){
        cin>>a[i];
    }
    int b[s];
    for(int i=0;i<s;i++){
        cin>>b[i];
    }
    int delta = m - n * k;
    map<int,int> good;
    for(int i=0;i<s;i++){
        good[b[i]]++;
    }
    map<int,int> cur;
    for(int i = 0; i < delta + k - 1; i++){
        cur[a[i]]++;
    }
    int curVal = 0;
    for(auto [v, q] : good){
        if(cur[v] >= q){
            curVal++;
        }
    }
    int needSize = good.size();
    vector<int> v;

    for(int i = delta + k -1; i < m ;i++){
        cur[a[i]]++;
        if(cur[a[i]]==good[a[i]]){
            curVal++;
        }
        if(curVal==needSize){
            v.push_back(i - delta - k + 1);
        }
        cur[a[i - delta - k + 1]]--;
        if(cur[a[i - delta - k +1 ]] + 1 == good[a[i -delta - k + 1]]) curVal--;
    }

    for(int i : v){
        if(i%k==0){
            bool del[delta + k] = {false};
            multiset<int> Set;
            for(int j=i;j<delta+k+i;j++){
                Set.insert(a[j]);
            }
            for(auto [v,q] : good){
                while(q--){
                    Set.extract(v);
                }
            }
            int curActive = s;
            while(curActive<k){
                Set.extract(Set.begin());
                curActive++;
            }
            for(int j=i;j<delta+k+i;j++){
                if(Set.find(a[j])!=Set.end()){
                    del[j-i] = true;
                    Set.extract(a[j]);
                }
            }
            vector<int> ans;
            for(int j = i; j<delta + k + i; j++){
                if(del[j-i]){
                    ans.push_back(j+1);
                }
            }
            cout<<ans.size()<<endl;
            for(int i : ans){
                cout<<i<<" ";
            }
            return 0;
        }
    }
    cout<<-1;
    return 0;
}