import java.util.Scanner;
public class meituan {
public static void main(String[] args) {
Scanner in = new Scanner(System.in);
int N = in.nextInt();
int[] nums = new int[N];
for(int i = 0; i < N; i++){
nums[i] = in.nextInt();
}
int K = in.nextInt();
int step = 0;
long[] dp = new long[N+1];
dp[0] = 0;
dp[1] = nums[0];
int index = 1;
for(int i = 2; i <=N; i++){
dp[i] = dp[i-1] + nums[index++];
}
int max = 0;
for(int i = 0; i <=N; i++){
for(int j = N; j>=i; j--){
if((dp[j] - dp[i])%K==0){
max = Math.max(max, j-i);
}
}
}
// for(int i = N-1; i>=0; i--){
// if(dp[i]%K==0){
// System.out.println(i+1);
// break;
// }
// }
System.out.println(max);
}
}