#include "bits/stdc++.h"
using namespace std;
#define int long long
#define FOR(i, a, b) for(int i=(a);i<(b);i++)
#define RFOR(i, a, b) for(int i=(b-1);i>=(a);i--)
#define REP(i, n) for(int i=0; i<(n); i++)
#define RREP(i, n) for(int i=(n-1); i>=0; i--)
#define REP1(i, n) for(int i=1; i<=(n); i++)
#define RREP1(i, n) for(int i=(n); i>=1; i--)
#define ALL(a) (a).begin(),(a).end()
#define UNIQUE_SORT(l) sort(ALL(l)); l.erase(unique(ALL(l)), l.end());
#define CONTAIN(a, b) find(ALL(a), (b)) != (a).end()
#define out(...) printf(__VA_ARGS__)
#define chmax(a,b) a = max(a,b)
#define chmin(a,b) a = min(a,b)
#if DEBUG
#define debug(...) printf(__VA_ARGS__)
#else
#define debug(...) /* ... */
#endif

void solve();
signed main()
{
#if DEBUG
    std::ifstream in("input.txt");
    std::cin.rdbuf(in.rdbuf());
#endif
    cin.tie(0);
    ios::sync_with_stdio(false);
    solve();
    return 0;
}

/*================================*/
#if DEBUG
#define SIZE 100
#else
#define SIZE 123450
#endif

int N,A,B;
template< class T >
struct Matrix {
    vector< vector< T > > A;
    
    Matrix() {}
    
    Matrix(size_t n, size_t m) : A(n, vector< T >(m, 0)) {}
    
    Matrix(size_t n) : A(n, vector< T >(n, 0)) {};
    
    size_t height() const {
        return (A.size());
    }
    
    size_t width() const {
        return (A[0].size());
    }
    
    inline const vector< T > &operator[](int k) const {
        return (A.at(k));
    }
    
    inline vector< T > &operator[](int k) {
        return (A.at(k));
    }
    
    static Matrix I(size_t n) {
        Matrix mat(n);
        for(int i = 0; i < n; i++) mat[i][i] = 1;
        return (mat);
    }
    
    Matrix &operator+=(const Matrix &B) {
        size_t n = height(), m = width();
        assert(n == B.height() && m == B.width());
        for(int i = 0; i < n; i++)
            for(int j = 0; j < m; j++)
                (*this)[i][j] += B[i][j];
        return (*this);
    }
    
    Matrix &operator-=(const Matrix &B) {
        size_t n = height(), m = width();
        assert(n == B.height() && m == B.width());
        for(int i = 0; i < n; i++)
            for(int j = 0; j < m; j++)
                (*this)[i][j] -= B[i][j];
        return (*this);
    }
    
    Matrix &operator*=(const Matrix &B) {
        size_t n = height(), m = B.width(), p = width();
        assert(p == B.height());
        vector< vector< T > > C(n, vector< T >(m, 0));
        for(int i = 0; i < n; i++)
            for(int j = 0; j < m; j++)
                for(int k = 0; k < p; k++)
                    C[i][j] = (C[i][j] + (*this)[i][k] * B[k][j]);
        A.swap(C);
        return (*this);
    }
    
    Matrix &operator^=(long long k) {
        Matrix B = Matrix::I(height());
        while(k > 0) {
            if(k & 1) B *= *this;
            *this *= *this;
            k >>= 1LL;
        }
        A.swap(B.A);
        return (*this);
    }
    
    Matrix operator+(const Matrix &B) const {
        return (Matrix(*this) += B);
    }
    
    Matrix operator-(const Matrix &B) const {
        return (Matrix(*this) -= B);
    }
    
    Matrix operator*(const Matrix &B) const {
        return (Matrix(*this) *= B);
    }
    
    Matrix operator^(const long long k) const {
        return (Matrix(*this) ^= k);
    }
    
    friend ostream &operator<<(ostream &os, Matrix &p) {
        size_t n = p.height(), m = p.width();
        for(int i = 0; i < n; i++) {
            os << "[";
            for(int j = 0; j < m; j++) {
                os << p[i][j] << (j + 1 == m ? "]\n" : ",");
            }
        }
        return (os);
    }
    
    
    T determinant() {
        Matrix B(*this);
        assert(width() == height());
        T ret = 1;
        for(int i = 0; i < width(); i++) {
            int idx = -1;
            for(int j = i; j < width(); j++) {
                if(B[j][i] != 0) idx = j;
            }
            if(idx == -1) return (0);
            if(i != idx) {
                ret *= -1;
                swap(B[i], B[idx]);
            }
            ret *= B[i][i];
            T vv = B[i][i];
            for(int j = 0; j < width(); j++) {
                B[i][j] /= vv;
            }
            for(int j = i + 1; j < width(); j++) {
                T a = B[j][i];
                for(int k = 0; k < width(); k++) {
                    B[j][k] -= B[i][k] * a;
                }
            }
        }
        return (ret);
    }
};
template<int MOD> struct ModInt {
    static const int Mod = MOD; unsigned x; ModInt() : x(0) { }
    ModInt(signed sig) { x = sig < 0 ? sig % MOD + MOD : sig % MOD; }
    ModInt(signed long long sig) { x = sig < 0 ? sig % MOD + MOD : sig % MOD; }
    int get() const { return (int)x; }
    ModInt &operator+=(ModInt that) { if ((x += that.x) >= MOD) x -= MOD; return *this; }
    ModInt &operator-=(ModInt that) { if ((x += MOD - that.x) >= MOD) x -= MOD; return *this; }
    ModInt &operator*=(ModInt that) { x = (unsigned long long)x * that.x % MOD; return *this; }
    ModInt &operator/=(ModInt that) { return *this *= that.inverse(); }
    ModInt operator+(ModInt that) const { return ModInt(*this) += that; }
    ModInt operator-(ModInt that) const { return ModInt(*this) -= that; }
    ModInt operator*(ModInt that) const { return ModInt(*this) *= that; }
    ModInt operator/(ModInt that) const { return ModInt(*this) /= that; }
    ModInt inverse() const { long long a = x, b = MOD, u = 1, v = 0;
        while (b) { long long t = a / b; a -= t * b; std::swap(a, b); u -= t * v; std::swap(u, v); }
        return ModInt(u); }
    bool operator==(ModInt that) const { return x == that.x; }
    bool operator!=(ModInt that) const { return x != that.x; }
    ModInt operator-() const { ModInt t; t.x = x == 0 ? 0 : Mod - x; return t; }
};
template<int MOD> ostream& operator<<(ostream& st, const ModInt<MOD> a) { st << a.get(); return st; };
template<int MOD> ModInt<MOD> operator^(ModInt<MOD> a, unsigned long long k) {
    ModInt<MOD> r = 1; while (k) { if (k & 1) r *= a; a *= a; k >>= 1; } return r; }
typedef ModInt<1000000007> mint;

void solve() {
    cin>>A>>B>>N;
    if (N<=1) {
        cout << N << endl;
        return;
    }
    auto m = Matrix<mint>(2,2);
    m[0][0]=A;
    m[0][1]=B;
    m[1][0]=1;
    m[1][1]=0;
    m ^= N;
    cout << m[1][0] << endl;
}