#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>
#define MAX 100 
 int main() {
     int t;
     if (scanf("%d", &t) != 1) {
         printf("Invalid input\n"); 
         return 0;
     }
     if (t<1||t > 100000) {
     printf("Invalid input\n");
     return 0;
     }
     int stack[MAX];
     int top=-1;
     char command[20];
     for (int i=0; i<t; i++) {
         scanf("%s", command);
         if (strcmp(command, "push") 0) {
             int x;
             scanf("%d", &x);
             if (top== MAX -1) {
                 continue;
                }
                 stack[++top] = x;
             } else if (strcmp(command, "pop") == 0) {
                 if (top==-1) {
                     printf("Stack is empty\n");
                 } else {
                     printf("%d\n", stack [top--]); 
                     } else if (strcmp(command, "display")==0) {
                         if (top==-1) {
                             printf("Stack is empty\n");
                             
                         } else {
                             for (int j top; j>=0; j--){
                                 printf("%d", stack[j]);
                                 if (j>0) printf(" ");
                             }
                             printf("\n");
                         } else {
                             printf("Invalid input\n");
                             return 0;
                         }
                     }     
                     return 0;
}