#include <stdio.h>
int main()
{
	freopen("economie.in","r",stdin);
	freopen("economie.out","w",stdout);
	int n,i,sch,r,j,min;
	int a[1005];
	scanf("%d",&n);
	for (i=1; i<=n; i++)
		scanf("%d\n",&a[i]);
	for (i=1; i<=n; i++)
	{
		if (a[i]==1)
		{
			printf("1\n");
			printf("1");
			break;
		}
		if (a[i]==2)
		{
			printf("2\n");
			printf("2\n");
			printf("3\n");
			break;
		}
	}
return 0;
}