#include<stdio.h>
int main(){
    int n;
    
    scanf("%d", &n);
    
    if(n < 0){
        printf("Invalid Input");
        return 0;
    }
    int stack[20], uniqur[20];
    int top = -1, uTop = -1;
    
    for(int i =0; i < N; i++){
        scanf("%d", &stack[++top]);
    }
    
    for (int i = 0; i<= top; i++){
        int found = 0;
        
    for(int j = 0; j <= uTop; j++){
        if(stack[i] == unique[j]){
            found = 1;
            break;
        }
      }
     if(!found){
        unique[++uTop] = stack[i];
     }
    }
    for(int i = 0; i <= uTop; i++){
        printf("%d\n",unique[i]);
    }
    
    return 0;
}