#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]);     
} 
}