#include<stdio.h>
#define max 100
int queue[max];
int front=-1,rear=-1;
void enqueue(int num){
    if(rear==max-1){
        printf("queue is full");
        return;
    }
    if(front==-1){
        front=0;
    }
    queue[++rear]=num;
}
void dequeue(){
    if(front==-1 || front>rear){
        printf("queue is empty");
        return;
    }
    while(queue[front]<0)
        printf("%d ",queue[front]);
    front++;
    }   

int main(){
    int n,num;
    scanf("%d",&n);
    if(n<=0){
        printf("Invalid input");
        return 0;
    }
    for(int i=0;i<n;i++){
        scanf("%d",&num);
        enqueue(num);
    }
    for(int i=0;i<n;i++)
        dequeue();
    return 0;
}