#include <fstream.h>
#include <math.h>
int ultim(long x)
	{
	long aux=x%10,a=x,cat=aux,i;
	x%=10;
	for (i=1;i<=a;i++)
		{
		x=x*a;
		if (x%10==aux) break;
		}
		cat=(x/a)%10;
	return cat;
	}

int main()
	{
	ifstream f("cifra.in");
	ofstream g("cifra.out");
	long cifra[10000],aux,t,n,i,j,max;
	f>>t;
	max=1;
	cifra[0]=0;
	for (i=1;i<=t;i++)
		{
		f>>n;
		for (j=max;j<=n;j++)
			{
			aux=ultim(j);
			cifra[j]=cifra[j-1]+aux;
			cifra[j]%=10;
			}
		if (j>max) max=j;
		g<<cifra[n]<<"\n";
		}
	f.close();
	g.close();
  return 0;
  }