func_code_string: #include <bits/stdc++.h>   using namespace std;   long long i, j, k, l, n, m, c, d, a[2005][2005], b[10005], f, mod = 1e9 + 7;   vector<long long> v;   int main() {     ios_base::sync_with_stdio(false);     cin.tie(NULL);     cout.tie(NULL);     cin >> n;     a[0][0] = 1;     for (i = 1; i <= n; i++)       for (j = 0; j <= i; j++) {         if (j - 1 < 0)           k = 0;         else           k = a[j - 1][i - 1];         a[j][i] = (k + a[j + 1][i - 1]) % mod;       }     for (i = n + 1; i <= 2 * n; i++)       for (j = 0; j <= n - (i - 1) % n - 1; j++) {         if (j - 1 < 0)           k = 0;         else           k = a[j - 1][i - 1];         a[j][i] = (k + a[j + 1][i - 1]) % mod;       }     for (i = 1; i <= 2 * n; i++) {       for (j = 0; j <= n; j++) b[i] = (b[i] + a[j][i]) % mod;     }     k = 0;     for (i = 1; i <= 2 * n; i = i + 2) k = (k + b[i]) % mod;     cout << k;   }   