int doubleFactorial(int n) { if (n == 0 || n == 1) return 1; else return n * doubleFactorial(n - 2); }
int main() { int n; cout << "Enter a natural number N: "; cin >> n;
int result; if (n % 2 == 0) { result = doubleFactorial(n); } else { result = doubleFactorial(n-1); } cout << "The double factorial of " << n << " is: " << result << endl; return 0;
using namespace std;
int doubleFactorial(int n) {
if (n == 0 || n == 1)
return 1;
else
return n * doubleFactorial(n - 2);
}
int main() {
int result;int n;
cout << "Enter a natural number N: ";
cin >> n;
if (n % 2 == 0) {
result = doubleFactorial(n);
} else {
result = doubleFactorial(n-1);
}
cout << "The double factorial of " << n << " is: " << result << endl;
return 0;
}