#include<cstdio>
#include<cstring>

FILE *f=fopen ("cifra.in","r");
FILE *g=fopen ("cifra.out","w");

int v[101];
char w[101];
int main (){
    int n,i,j,lg,x,y,s;
   
	fscanf(f,"%d",&n);
    
	for(i=1;i<=100;++i){
        s=1;
        for(j=1;j<=i;++j){
            s=(s*i)%10;
		}
        v[i]=(s+v[i-1])%10;
    }
    while(n){
        n--;
        fscanf(f,"%s",&w);
        lg=strlen(w);
        x=0;
        y=w[lg-1]-'0';
        if(lg>1){
            x=w[lg-2]-'0';
		}
        fprintf(g,"%d\n",v[x*10+y]);
    }
    return 0;
 
}