#include<stdio.h>

int main()

{
    int n;
    scanf("%d",&n);
    int arr[n],ans[n];
    for(int i=0;i<n;scanf("%d",&arr[i++]));
    for(int i=0;j<n;i++)
    {
        ans[i]=ans[i]+1;
        printf("%d",ans[i]);
    }
    for(int i=0;i<n;i++)
    {
        //if(arr[i]!=ans[i])
        printf("%d",ans[i]);
    }
    
}