func_code_string: #include <bits/stdc++.h>   using namespace std;   unsigned long long n, a = 1, b = 1, mod = 1000000007, pp = 1000000005;   unsigned long long fp(unsigned long long n, unsigned long long p) {     if (p == 0) return 1;     if (p == 1) return n;     unsigned long long res;     res = fp(n, p / 2) % mod;     res = (res * res) % mod;     if (p % 2) res = (res * n) % mod;     return res % mod;   }   long long solve(long long n, long long m) {     unsigned long long a = 1, b = 1, res;     for (int i = 1; i <= m; i++) {       a *= n;       a %= mod;       n--;       b *= i;       b %= mod;     }     res = (a * fp(b, pp) % mod) % mod;     return res;   }   int main() {     ios::sync_with_stdio(0);     cin.tie(0), cout.tie(0);     ios_base::sync_with_stdio(0);     ;     cin >> n;     unsigned long long ans = solve(2 * n, n);     cout << (ans % mod - n) % mod <<   n ;     return 0;   }   