#include //#include using namespace std; //using Graph = vector>; using dou =long double; string yes="yes"; string Yes="Yes"; string YES="YES"; string no="no"; string No="No"; string NO="NO"; template inline bool chmax(T& a, T b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(T& a, T b) { if (a > b) { a = b; return true; } return false; } typedef long long ll; typedef pair P; typedef pair PL; const ll mod = 1000000007; //const ll mod = 998244353; struct mint { ll x; // typedef long long ll; mint(ll x=0):x((x%mod+mod)%mod){} mint operator-() const { return mint(-x);} mint& operator+=(const mint a) { if ((x += a.x) >= mod) x -= mod; return *this; } mint& operator-=(const mint a) { if ((x += mod-a.x) >= mod) x -= mod; return *this; } mint& operator*=(const mint a) { (x *= a.x) %= mod; return *this;} mint operator+(const mint a) const { return mint(*this) += a;} mint operator-(const mint a) const { return mint(*this) -= a;} mint operator*(const mint a) const { return mint(*this) *= a;} mint pow(ll t) const { if (!t) return 1; mint a = pow(t>>1); a *= a; if (t&1) a *= *this; return a; } // for prime mod mint inv() const { return pow(mod-2);} mint& operator/=(const mint a) { return *this *= a.inv();} mint operator/(const mint a) const { return mint(*this) /= a;} }; istream& operator>>(istream& is, const mint& a) { return is >> a.x;} ostream& operator<<(ostream& os, const mint& a) { return os << a.x;} #define rep(i, n) for(ll i = 0; i < (int)(n); i++) #define brep(n) for(int bit=0;bit<(1<= (ll)0ll; i--) #define rrep(i,m,n) for(ll i = m; i < (ll)(n); i++) #define reprep(i,j,h,w) rep(i,h)rep(j,w) #define all(x) (x).begin(),(x).end() #define VEC(type,name,n) std::vector name(n);rep(i,n)std::cin >> name[i]; #define pb push_back #define pf push_front #define query int qq;std::cin >> qq;rep(qqq,qq) #define lb lower_bound #define ub upper_bound #define fi first #define se second #define itn int #define mp make_pair #define sum(a) accumulate(all(a),0ll) #define keta fixed< > name(m,vector (n,a)) //#define vvector(name,typ,m,n)vector > name(m,vector (n)) #define vvvector(name,t,l,m,n,a) vector > > name(l, vector >(m, vector(n,a))); #define vvvvector(name,t,k,l,m,n,a) vector > > > name(k,vector > >(l, vector >(m, vector(n,a)) )); #define case std::cout <<"Case #" < tのget関数はget(t) //resizeはメンバ関数 int main(){ ll a,b,n; std::cin >> a>>b>>n; if(n%3==0)std::cout << a << std::endl; if(n%3==1)std::cout << b << std::endl; if(n%3==2)std::cout << ll(a^b) << std::endl; }