#include<stdio.h>
#define max 20;
int arr[max];
int rear=-1,front=-1;
void enqueue(int num){
    if(front == -1 && rear == -1){
        front = rear = 0;
        arr[rear] = num;
    }
    else{
        arr[++rear] = num;
    }
}
void display(){
    for(int i=front; i<=rear;i++){
        if(arr[i]<0){
            printf("%d",arr[i]);
        }
    }
    for(int i=front; i<=rear; i++){
        if(arr[i]<0){
            printf("%d",arr[i]);
        }
    }
}
int main(){
    int size,num;
    scanf("%d",&size);
    if(size<0){
        printf("Invalid input");
        return 0;
    }
    for(int i=0; i<size; i++){
        scanf("%d",&num);
        enqueue(num);
    }
    display();
    return 0;
}