codeforces543A Writing Code(完全揹包)

//完全揹包
//首先定義dp[i][j][k]爲前i個人寫j行所含bug爲k個的種數
//然後對於dp[i][j][k]=dp[i-1][j][k]+dp[i][j-1][k-bug[i]];//第i個人要麼不寫，要麼再寫一行
//然後用類似完全揹包我們可以通過順序遍歷，省掉一維i
import java.io.*;
import java.util.*;

public class cf {
    FastScanner in;
    long max(long a,long b){
        if(a>b)return a;
        return b;
    }
    void input(){
        in = new FastScanner(System.in);
        int n=in.nextInt();
        int m=in.nextInt();
        int b=in.nextInt();
        int mod=in.nextInt();
        int v[]=new int[3000];
        int dp[][]=new int[600][600];
        int cnt=0;
        for(int i=1;i<=n;i++){
            v[i]=in.nextInt();
        }
        dp[0][0]=1;
        for(int i=1;i<=n;i++){
            for(int j=1;j<=m;j++){
                for(int k=v[i];k<=b;k++){
                    dp[j][k]=(dp[j][k]+dp[j-1][k-v[i]])%mod;
                }
            }
        }
        int ans=0;
        for(int i=0;i<=b;i++){
            ans=(ans+dp[m][i])%mod;
        }
        System.out.println(ans);
        
    }
    public static void main(String[] args){
        new cf().input();
    }
}
class FastScanner {
    BufferedReader br;
    StringTokenizer st;

    public FastScanner(File f) {
        try {
            br = new BufferedReader(new FileReader(f));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }

    public FastScanner(InputStream f) {
        br = new BufferedReader(new InputStreamReader(f));
    }

    String next() {
        while (st == null || !st.hasMoreTokens()) {
            String s = null;
            try {
                s = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (s == null)
                return null;
            st = new StringTokenizer(s);
        }
        return st.nextToken();
    }

    boolean hasMoreTokens() {
        while (st == null || !st.hasMoreTokens()) {
            String s = null;
            try {
                s = br.readLine();
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (s == null)
                return false;
            st = new StringTokenizer(s);
        }
        return true;
    }

    int nextInt() {
        return Integer.parseInt(next());
    }

    long nextLong() {
        return Long.parseLong(next());
    }

    double nextDouble() {
        return Double.parseDouble(next());
    }
    String nextLine() {
        
        String str = "";
        try {
            str = br.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return str;
    }
}