#include <stdio.h>  
#include <string.h>  

int main()  
{  
   freopen("cifra.in","r",stdin);  
   freopen("cifra.out","w",stdout);  
   int x,n,i,s=0,r,j,p,t,rr;  
   char sir[101];  
   
   while(t){
     s=0;  
     scanf("%s",sir);  
     n = strlen(sir);  
     if (n==1)   
        x = sir[0]-'0'+0;  
     else  
        x = 10 * (sir[n-2]-'0') + sir[n-1]-'0';  
     s = x/20*4%10;  
     r = x%20;  
     
     for(i=1; i<=r; i++)
     {  
        p=1;  
        rr = i%4;  
        if(rr == 0)  
           rr = 4;  
        for (j=1;j <= rr;j++)  
           p = p * (i%10) % 10;  
        s = (s+p) % 10;  
    }  
    printf("%d\n",s);  
    t--;  
  }  
  return 0;  
}