#include <stdio.h>
#include <stdlib.h>

typedef struct Node {
    int id;
    struct Node* next;
} Node;

int main() {
    int n, x, i;
    scanf("%d", &n);
    
    if (n < 0) {
        printf("Invalid input\n");
        return 0;
    }
    
    Node* head = NULL, *tail = NULL;
    for (i = 0; i < n; i++) {
        scanf("%d", &x);
        Node* node = (Node*)malloc(sizeof(Node));
        node->id = x;
        node->next = NULL;
        if (!head) {
            head = tail = node;
        } else {
            tail->next = node;
            tail = node;
        }
    }
    
    Node* current = head;
    while (current) {
        Node* checker = current->next;
        Node* prev = current;
        while (checker) {
            if (checker->id == current->id) {
                Node* del = checker;
                prev->next = checker->next;
                checker = checker->next;
                free(del);
            } else {
                prev = checker;
                checker = checker->next;
            }
        }
        current = current->next;
    }
    
    Node* temp = head;
    while (temp) {
        printf("%d", temp->id);
        if (temp->next) printf("\0");
        temp = temp->next;
    }
    printf("\n");
    
    return 0;
}