#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<iostream>
#include<cstdio>
#include<cmath>
#include<string>
#include<queue>
#include<algorithm>
#include<stack>
#include<cstring>
#include<vector>
#include<list>
#include<set>
#include<map>
using namespace std;
#define ll long long
#define pi (4*atan(1.0))
#define eps 1e-14
#define bug(x)  cout<<"bug"<<x<<endl;
const int N=2e5+10,M=1e6+10,inf=1e9+7;
const ll INF=1e18+10,mod=1e9+7;
ll MOD;
struct Matrix
{
    ll a[2][2];
    Matrix()
    {
        memset(a,0,sizeof(a));
    }
    void init()
    {
        for(int i=0;i<2;i++)
            for(int j=0;j<2;j++)
                a[i][j]=(i==j);
    }
    Matrix operator + (const Matrix &B)const
    {
        Matrix C;
        for(int i=0;i<2;i++)
            for(int j=0;j<2;j++)
                C.a[i][j]=(a[i][j]+B.a[i][j])%MOD;
        return C;
    }
    Matrix operator * (const Matrix &B)const
    {
        Matrix C;
        for(int i=0;i<2;i++)
            for(int k=0;k<2;k++)
                for(int j=0;j<2;j++)
                    C.a[i][j]=(C.a[i][j]+1LL*a[i][k]*B.a[k][j])%MOD;
        return C;
    }
    Matrix operator ^ (const ll &t)const
    {
        Matrix A=(*this),res;
        res.init();
        ll p=t;
        while(p)
        {
            if(p&1)res=res*A;
            A=A*A;
            p>>=1;
        }
        return res;
    }
};
ll quickmod(ll a,ll b,ll c)
{
    ll ans=1;
    while(b)
    {
        if(b&1)ans=(ans*a)%c;
        b>>=1;
        a=(a*a)%c;
    }
    return ans;
}
int main()
{
    ll a,b,n;
    Matrix base,ans;
    base.a[0][0]=1;base.a[0][1]=1;
    base.a[1][0]=1;base.a[1][1]=0;
    MOD=1e9+6;
    while(~scanf("%lld%lld%lld",&a,&b,&n))
    {
        if(n==0)
            printf("%lld\n",a);
        else if(n==1)
            printf("%lld\n",b);
        else
        {
            ans=base^(n-1);
            ll x=quickmod(b,ans.a[0][0],1e9+7);
            ll y=quickmod(a,ans.a[0][1],1e9+7);
            printf("%lld\n",(x*y)%mod);
        }
    }
    return 0;
}