A_-_A_Recursive_Function.cpp

#include<bits/stdc++.h>
using namespace std;

#define endl            "\n"
#define Code            ios_base::sync_with_stdio(false);
#define By              cin.tie(NULL);
#define Nasif           cout.tie(NULL)
#define ll              long long int
#define pb              push_back
#define mp              make_pair
#define Gcd(a,b)        __gcd(a, b)
#define Lcm(a,b)        (a*b) / Gcd(a,b)
#define mem(a,b)        memset(a, b, sizeof(a))//a is array or vector;b is the value that wants to set
#define show(...)       __f (#__VA_ARGS__, __VA_ARGS__)

template <typename Arg1>//show(parameters)
void __f (const char* name, Arg1&& arg1) { cout << name << ": " << arg1 << endl; }
template <typename Arg1, typename... Args>
void __f (const char* names, Arg1&& arg1, Args&&... args){ const char* comma = strchr (names + 1, ',');cout.write (names, comma - names) << ": " << arg1 << " | "; __f (comma + 1, args...);}


int factorial(int n)
{
	// single line to find factorial
	return (n == 1 || n == 0) ? 1 : n * factorial(n - 1);
}

// Driver Code
int main()
{
    Code By Nasif;
	int n;
    cin>>n;
	cout << factorial(n);
	return 0;
}