#include <stdio.h>
#include <stdint.h>
#include <string.h>
#define MAX 10
typedef struct {
int arr[MAX];
int top;
int capacity;
} Stack;
void push(Stack *s, int x) {
if (s->top == s->capacity-1) {
printf("Stack Overflow\n");
return;
}
s->arr[++s->top] = x;
}
void pop(Stack *s) {
if (s->top == -1) {
printf("Stack Underflow\n");
return;
}
printf("%d\n",s->arr[s->top--]);
}
void process_stack(int n) {
// Your logic here
Stack s = {.top = -1, .capacity = MAX};
for (int i = 0; i < n; i++) {
char op[4];
scanf("%s", op);
if (strcmp(op, "push") == 0) {
int x;
scanf("%d", &x);
push(&s, x);
} else {
pop(&s);
}
}
}
int main() {
int n;
scanf("%d", &n);
getchar(); // Consume newline after number
process_stack(n);
return 0;
}