char s[100010];
n,i,t,ans,c2,c3;
p2[]={1,2,4,8,7,5};
f2(n){int i=0;for(;n&&n%2==0;n/=2)i++;return i;}
f3(n){int i=0;for(;n&&n%3==0;n/=3)i++;return i;}
main(){
	for(gets(s);gets(s);){
		n=strlen(s)-1;
		t=ans=c2=c3=0;
		for(i=0;i<=n;i++){
			//Σ(nCi*s[i]%9)を求めたい
			t+=s[i]-48;
			ans+=p2[c2%6]*(c3?c3==1?3:0:1)*(s[i]-48)%9;
			c2+=f2(n-i)-f2(i+1);
			c3+=f3(n-i)-f3(i+1);
		}
		printf("%d\n",ans%9?:t?9:0);
	}
}