func_code_string: #include <bits/stdc++.h>   using namespace std;   long long n, ans, fact[200005];   long long pangkat(long long a, long long b) {     if (b == 0) return 1;     long long temp = pangkat(a, b / 2);     if (b % 2 == 0) return (temp * temp) % 1000000007;     return (((temp * temp) % 1000000007) * a) % 1000000007;   }   long long comb(long long a, long long b) {     long long temp = (fact[b] * fact[a - b]) % 1000000007;     return (fact[a] * pangkat(temp, 1000000007 - 2)) % 1000000007;   }   int main() {     ios_base::sync_with_stdio(0);     cin.tie(0);     cout.tie(0);     cin >> n;     fact[0] = 1;     for (int i = 1; i <= 2 * n; i++) fact[i] = (fact[i - 1] * i) % 1000000007;     ans = 2 * comb(2 * n - 1, n) - n;     cout << ans % 1000000007 <<   n ;   }   