279. 自然数拆分

https://www.acwing.com/problem/content/submission/code_detail/13028632/

AcWing/279/279.cpp

@@ -0,0 +1,28 @@
+#include <iostream>
+
+using std::cin;
+using std::cout;
+const char endl = '\n';
+
+const int N = 4005;
+const long long mod = 2147483648;
+
+int n;
+long long f[N];
+
+int main() {
+    std::ios::sync_with_stdio(false);
+
+    cin >> n;
+
+    f[0] = 1;
+    for (int i = 1; i <= n; i++) {
+        for (int j = i; j <= n; j++) {
+            f[j] = (f[j] + f[j - i]) % mod;
+        }
+    }
+
+    cout << f[n] - 1 << endl;
+
+    return 0;
+}