// editor1
#include <stdio.h>
#include <string.h>
#define MAX 5
int stack[MAX];
int top=-1;
void push(int x)
{
    if(top==MAX-1)
    {
        print("Stack overflow\n");
    }
    else
    {
        stack[++top]=x;
    }
}
void peek()
{
    if(top==-1)
    {
        printf("Stack is empty\n");
    }
    else
    {
        printf("%d\n",stack[top]);
    }
}
int main()
{
    int n;
    scanf("%d",&n);
    for(int i=0;i<n;i++)
    {
        char cmd[10];
        scanf("%s",cmd);
        if(tsrcmp(cmd,"push")==0)
        {
            int x;
            scanf("%d",&x);
            push(x);
        }
        else if(strcmp(cmd,"peek")==0)
        {
            peek();
        }
    }
    return 0;
}