#include <cstdio>
#include <cstring>

#define file_in "cifra.in"
#define file_out "cifra.out"

int i,j,Q,n,nr,x,v[1111];
char s[10100];

int main(){
	
	freopen(file_in,"r",stdin);
	freopen(file_out,"w",stdout);
	
	n=0;
	for (i=1;i<100;++i){
		
		x=i;
		for(j=1;j<i;++j) 
			x=x%10*i;
		n+=x;
		n%=10;
		v[i]=n;
	}
	
	scanf("%d\n", &Q);
	
	while(Q--){
		
		gets(s);
		n=strlen(s);
		if (n==1)
			printf("%d\n", v[s[0]-'0']);
		else
			printf("%d\n", v[(s[n-2]-'0')*10+s[n-1]-'0']);
	}
	
	return 0;
	
}