func_code_string: #include <bits/stdc++.h>   using namespace std;   long long fact[3000002], n, inv[3000002];   long long pw(long long b, long long e) {     long long ans = 1;     while (e) {       if (e & 1) ans = (ans * b) % 1000000007;       b = (b * b) % 1000000007;       e >>= 1;     }     return ans;   }   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     int n;     cin >> n;     ++n;     fact[0] = inv[0] = 1;     for (int i = 1; i <= 2500000; ++i) {       fact[i] = (fact[i - 1] * i) % 1000000007;       inv[i] = pw(fact[i], 1000000007 - 2);     }     long long ans = 2LL * fact[2 * n - 1] * inv[n];     ans %= 1000000007;     ans = ans * inv[n - 1];     ans %= 1000000007;     cout << (ans - 1 + 1000000007) % 1000000007;     return 0;   }   