'commit'

TangDou/AcWing/Math/ZhuHeJiShu/CatalanNumberPaiDui.cpp

@@ -0,0 +1,18 @@
+#include <bits/stdc++.h>
+using namespace std;
+typedef long long LL;
+
+LL C(int n, int m) {
+    LL a = 1, b = 1;
+    for (int i = 0; i < m; i++) {
+        a *= (n - i);
+        b *= (m - i);
+    }
+    return a / b;
+}
+int main() {
+    int n;
+    cin >> n; // n过大会溢出，需要结合高精度
+    printf("%lld\n", C(2 * n, n) / (n + 1));
+    return 0;
+}