#include<bits/stdc++.h>
using namespace std;
using ll = long long;
#define chmax(a,b) a = max(a,b)

pair<int,int> calc(int a,int b){
    return make_pair(min(a,b),max(a,b));
}
int main(){
    int n,k,x,y;
    cin>>n>>k>>x>>y;
    vector<int> a(n);
    for(int i = 0;i<n;i++) cin>>a[i];
    map<pair<int,int>,int> d;
    vector<int> b(n+2);
    x %= k;
    y %= k;
    b[0] = x % k;
    b[1] = y % k;
    for(int i = 0;i<n;i++) b[i+2] = a[i] % k;
    unordered_map<int,set<pair<int,int>>>s;
    d[make_pair(min(x,y),max(x,y))] = 0;
    s[(x+y)%k].insert(make_pair(min(x,y),max(x,y)));
    int ans = 0;
    vector<vector<int>> tmp(n+2,vector<int>(k+1,-1e9));
    tmp[0][y] = 0;
    tmp[1][x] = 0;
    vector<int> cnt(n+2,0);
    for(int i = 0;i<n;i++){
        int now = b[i+2];
        for(int j = 0;j<i+2;j++){
            int nxt = b[j];
            int need = 2 * k - nxt - now;
            need %= k;
            int can = max(tmp[j][need]+1,cnt[j]);
            chmax(tmp[i+2][nxt],can);
            chmax(cnt[i+2],can);
            ans = max(ans,can);
        }
    }
    cout<<ans<<endl;
}