#include using namespace std; #define FOR(i, s, n) for(int i = s; i < (int)n; ++i) #define per(i, n) for(int i = n; i >= 0; i--) #define ROF(i, s, n) for(int i = s; i >= (int)n; i--) #define FORIT(i, A) for (auto i : A) #define PRINT(x) cout << (x) << "\n" #define ALL(a) (a).begin(),(a).end() #define RALL(a) (a).rbegin(), (a).rend() #define MP make_pair #define PB push_back #define EACH(i, n) for (__typeof((n).begin()) i = (n).begin(); i != (n).end(); ++i) #define SZ(a) int((a).size()) #define EXIST(s,e) ((s).find(e)!=(s).end()) #define SORT(c) sort((c).begin(),(c).end()) #define CLR(a) memset((a), 0 ,sizeof(a)) #define NCLR(a) memset((a), -1 ,sizeof(a)) #define sq(n) (n) * (n) typedef vector VI; typedef vector VVI; typedef vector VS; typedef pair PII; typedef long long LL; typedef vector VLL; typedef vector VVLL; typedef unsigned int uint; typedef unsigned long long ull; typedef priority_queue maxpq; typedef priority_queue< int, vector, greater > minpq; typedef complex Point; static const double EPS = 1e-10; static const double PI = acos( -1.0 ); static const int mod = 1000000007; static const int INF = 1 << 29; static const LL LL_INF = 1ll << 60; static const int dx[] = { -1, 0, 1, 0, 1, -1, 1, -1 }; static const int dy[] = { 0, -1, 0, 1, 1, 1, -1, -1 }; #ifdef WIN32 #define dump(x) cerr << #x << " = " << (x) << "\n" #define debug(x) cerr << #x << " = " << (x) << " (L" << __LINE__ << ")" << " " << __FILE__ << "\n" #else #define dump(x) #define debug(x) #endif LL f0, f1, n; void input() { scanf( "%lld %lld %lld", &f0, &f1,&n ); } void solve() { LL dp[ 3 ] = { f0, f1, f1 ^ f0 }; printf( "%lld\n", dp[ n % 3 ] ); } int main() { input(); #ifdef WIN32 clock_t stime = clock(); #endif solve(); #ifdef WIN32 clock_t etime = clock(); fprintf(stderr,"TIME : %f\n", ( double ) ( etime - stime ) / CLOCKS_PER_SEC); #endif return 0; }