AZ contest 3-4, High school maths

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

#define int long long int
#define LD long double

const int N = 100010;

int inf = 1e9;
int mod = 1e9 + 9;

inline void add(int &a, int b) {
    a += b;
    if (a >= mod) a -= mod;
}

inline void sub(int &a, int b) {
    a -= b;
    if (a < 0) a += mod;
}

inline int mul(int a, int b) {
    return (int) ((long long) a * b % mod);
}

inline int power(int a, int b) {
    int res = 1;
    while (b) {
        if (b%2 == 1) {
            res = mul(res, a);
        }
        a = mul(a, a);
        b/=2;
    }
    return res;
}


signed main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int t;
    cin>>t;
    while(t--){
        int a,b,n;
        cin>>a>>b>>n;
        int ans = 0;

        if(a == 1){
            ans = mul(n,b);
            cout<<(1 + ans)%mod<<"\n";
        }
        else{
            add(ans, power(a,n+1));

            add(ans, mul(power(a,n), (b-1)));

            sub(ans, b);

            ans = mul(ans, power(a-1, mod-2));

            cout<<ans<<"\n";
        }
    }
    return 0;
}