#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; typedef unsigned long long ull; #define FOR(i,a,b) for(int i=(a);i<(b);i++) #define REP(i,n) FOR(i,0,n) #define CLEAR(d) memset((d), 0, (sizeof((d)))) #define ALL(c) (c).begin(), (c).end() #define ABS(x) ((x < 0) ? -(x) : (x)) #define SORT(x) sort((x).begin(), (x).end()) #define RSORT(x) sort((x).begin(), (x).end(), greater() ) #define SIZE(a) ((int)((a).size())) #define MAX3(a, b, c) (max(max((a), (b)), (c))) #define MIN3(a, b, c) (min(min((a), (b)), (c))) #define MOD 1000000007 #define EPS 1e-5 #define PI (acos(-1)) #define INF 10000000 struct edge { int to; int cost; }; //=================================================== int main() { ll f[3], n; cin >> f[0] >> f[1] >> n; f[2] = f[0] ^ f[1]; cout << f[n%3] << endl; return 0; }