lcm WA

#include <bits/stdc++.h>
using namespace std;
#define ll long long int
#define Faster  ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
template <typename T> T Gcd(T a,T b){if(a<0)return Gcd(-a,b);if(b<0)return Gcd(a,-b);return (b==0)?a:Gcd(b,a%b);}
template <typename T> T Lcm(T a,T b) {if(a<0)return Lcm(-a,b);if(b<0)return Lcm(a,-b);return a*(b/Gcd(a,b));}

ll a[1000008];
ll lastd(ll x)
{
    while(x%10==0)
    {
        x/=10;
    }
    return x%10;
}
int main()
{
   Faster
   ll n,c,d,e,f,i,j,k,l;
   ll ans=1;
   for(ll i=1;i<1000001;i++)
   {
        e=i;
        c=Lcm(i,ans);
        ans=c;
        a[e]=lastd(c);
   }
   while(cin>>n && n)
   {
       cout<<a[n]<<endl;
   }
   return 0;
}