import java.util.*;

public class Main{
  	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
 
		int N = sc.nextInt();			//N
 		int[] A = new int[N];
      	int num = 0;
      	for(int i=0;i<N;i++){
          int j = 0;
          int k = sc.nextInt();
          while(j<num&&A[j]!=k){
            j++;
          }
          if(j>=num){
            A[j]=k;
            num++;
          }
        }
      System.out.println(num);
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz