#include<stdio.h>
#include<string.h>
int t,i,j,L,e,p,x[100]; 
char s[120],*c;
void read(),solve();
int main()
{    
read();    
solve();    
return 0; } 
void read() {   
freopen("cifra.in","r",stdin);  
freopen("cifra.out","w",stdout);   
scanf("%d",&t);
}
void solve()
{      
for(i=0;i<20;i++){e=i&3?i&3:4;p=i;for(j=1;j<e;j++)p*=i;p%=10;x[i]=x[i+20]=x[i+40]=x[i+60]=x[i+80]=p;}    
for(i=1;i<100;i++){x[i]+=x[i-1];x[i]=x[i]<10?x[i]:x[i]-10;}    
s[0]=s[1]='0';c=s+2;    
for(;t;t--)    
{        
scanf("%s",c);        
L=strlen(s);        
i=10*(s[L-2]-'0')+(s[L-1]-'0');        
printf("%d\n",x[i]);    
}
}