func_code_string: #include <bits/stdc++.h>   #pragma GCC optimize( Ofast ,  unroll-loops ,  no-stack-protector )   using namespace std;   int32_t main() {     ios::sync_with_stdio(false);     cin.tie(0);     cout.tie(0);     long long test = 1;     while (test--) {       long long x, y;       cin >> x >> y;       long long n;       cin >> n;       long long hash[7];       hash[0] = 0;       hash[1] = x;       hash[2] = y;       hash[3] = (y - x + 1000000007) % 1000000007;       hash[4] = (-1 * x + 1000000007) % 1000000007;       hash[5] = (-1 * y + 1000000007) % 1000000007;       hash[6] = (x - y + 1000000007) % 1000000007;       long long rem = (n) % 6;       if (rem == 0) rem = 6;       long long ans = hash[rem];       cout << (ans + 1000000007) % 1000000007;     }     cerr << endl          <<  Time:   << (clock() * 1000. / CLOCKS_PER_SEC) <<   ms  << endl;     return 0;   }   