#include<stdio.h>
#include<stdlib.h>

int trans(float *a,int i,int n)
{
	float pom;
	if ((n%2==0)&&(i==n)) {  return 1; }
	else if ((n%2==1)&&(i==n-1)) {  pom=a[i]; a[i]=a[i+1]; a[i+1]=pom; return 1; }
	else { pom=a[i]; a[i]=a[i+1]; a[i+1]=pom; i=i+2; trans(a,i,n); }

}

main()
{
	int i,n; float *a;
	scanf("%d",&n);
	a=(float *)malloc(n*sizeof(float));
	for(i=0;i<n;i++)
	scanf("%f",&a[i]);
	trans(a,0,n-1);
	for(i=0;i<n;i++)
	printf("%.2f\n",a[i]);
}