#include <bits/stdc++.h> using namespace std; string gt[2001]; string multiplys(string s, int x) { string res(s.length(), '0'); int nho = 0; for (int i = s.length() - 1; i >= 0; i--) { nho += (s[i] - '0') * x; res[i] = (nho % 10) + '0'; nho /= 10; } if (nho) res = to_string(nho) + res; return res; } string sub(string a, string b) { int na = a.length(), nb = b.length(); int n = max(na, nb); if (na < n) a.insert(0, string(n - na, '0')); if (nb < n) b.insert(0, string(n - nb, '0')); int borrow = 0, s; string c(n, '0'); for (int i = n - 1; i >= 0; i--) { s = (a[i] - '0') - (b[i] - '0') - borrow; if (s < 0) { s += 10; borrow = 1; } else borrow = 0; c[i] = char(s + '0'); } while (c.length() > 1 && c[0] == '0') c.erase(c.begin()); return c; } string add(string a, string b) { int na = a.length(), nb = b.length(); int n = max(na, nb); if (na < n) a.insert(0, string(n - na, '0')); if (nb < n) b.insert(0, string(n - nb, '0')); string res(a.length(), '0'); int nho = 0; for (int i = a.length() - 1; i >= 0; i--) { nho += a[i] - '0' + b[i] - '0'; res[i] = (nho % 10) + '0'; nho /= 10; } if (nho) res = '1' + res; return res; } int cmp(string a, string b) { int na = a.length(), nb = b.length(); int n = max(na, nb); if (na < n) a.insert(0, string(n - na, '0')); if (nb < n) b.insert(0, string(n - nb, '0')); if (a == b) return 0; if (a > b) return 1; return -1; } string div(string a, string b) { string k[11], mem = "", c = ""; for (int i = 1; i < 11; i++) k[i] = add(k[i - 1], b); int n = a.length(); for (int i = 0; i < n; i++) { mem = mem + a[i]; int j = 1; while (cmp(mem, k[j]) != -1) j++; c = c + to_string(j - 1); mem = sub(mem, k[j - 1]); } while (c.length() > 1 && c[0] == '0') c.erase(c.begin()); return c; } string multiply(string a, string b) { string res = ""; if (a == "0" || b == "0") { return "0"; } int cnt = 0; int i = a.length() - 1; while (i >= 0) { int nho = 0; int j = b.length() - 1; string s(b.length(), '0'); while (j >= 0) { nho += (a[i] - '0') * (b[j] - '0'); s[j] = (nho % 10) + '0'; nho /= 10; j--; } if (nho) s = to_string(nho) + s; string Them_vao_sau(cnt, '0'); s = s + Them_vao_sau; res = add(res, s); cnt++; i--; } return res; } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); gt[0] = "1"; for (int i = 1; i <= 2001; i++) gt[i] = multiplys(gt[i - 1], i); int n; cin >> n; string res = div(gt[2 * n], multiply(gt[n + 1], gt[n])); cout << res; }