#include<stdio.h>
#include<stdlib.h>
struct cus
{
    int id;
    int time;
};
int main()
{
    struct cus s;
    int n;
    scanf("%d",&n);
    if(n<0)
    {
        printf("Invalid input");
    }
    for(int i=0,i<n,i++)
    {
        scanf("%d",&id.s[i]);
        if(id.s[i]<0)
        {
            printf("Invalid input");
        }
        scanf("%d",&time.s[i]);
        if(time.s[i]<0)
        {
            printf("Invalid input");
        }
    }
    for(int i=0;i<n;i++)
    {
        printf("%d\n",id.s[i]);
    }
}