Road-signs problem

#include <bits/stdc++.h>
using namespace std;
#define ll long long

ll large=1000000007;
bool distinct(ll i,ll k)
{
    set<ll>s;
    while(i>0)
    {
        s.insert(i%10);
        if(s.size()>2)
        {
            return false;
        }
        i/=10;
    }
    if(i==0)
    {   
            while(k>0)
            {
                s.insert(k%10);
                if(s.size()>2)
                {
                    return false;
                }
                k/=10;
            }
            if(k==0 && s.size()==2){
                return true;
            }
        
    }
     return false;
}

int main() {
	// your code goes here
	ll t;
	cin>>t;
	while(t--)
	{
	    ll k,n=0;
	    cin>>k;
	    ll l=pow(10,k)-1;
	    for(ll i=0;i<=l/2;i=i+1)
	    {
	        if(distinct(i,l-i)==true)
	        {
	              n=n+2;
	        }
	    }
	    ll ans=(n+2)%large;
	    cout<<ans<<"\n";
	}
	return 0;
}