#include<stdio.h>
 int mani()
 {
 	int n;int i;int a[n];
 	scanf("%d",&n);
 	scanf("%d",a);
 	if(n%2)
 	{
for(i=n;i>=0;i-2)
 	printf("%d",a[i-1]);
 	for(i=n-1;i>=0;i-2)
 	printf("%d",a[i-1]);
 	}
 	else
 	{for(i=n;i>=0;i-2)
 	printf("%d",a[i-1]);
 	for(i=n-1;i>=0;i-2)
 	printf("%d",a[i-1]);
 	}
 	return 0;
 }