Go: package main

import (
        "fmt"
)

func main() {
        var n int
        fmt.Scanf("%d", &n)
        fmt.Println(fact(n))
}

func fact(n int) (f uint64) {
        if n < 2 {
                return uint64(1)
        } else {
                return fact(n-1) * uint64(n)
        }
}

C++: #include<iostream>
using namespace std;

int main()

{

    int num;
	unsigned long long int total=1;

    cout << "Please enter a number : ";
    cin >> num;

    for(int i=1; i<=num; i++)
    {
        total*=i;
    }

	printf("%llu", total);
	
    return 0;
}

C++: #include<stdio.h>

int main(void){

    int n,i;
    long long ans = 1;
    scanf("%d", &n);

    for(i = 1; i <= n; i++){
        ans *= i;
    }
    printf("%lld\n", ans);
    return 0;
}

C++: #include<iostream>
using namespace std;

int factorial(int n){
  if(n==0)return 1;
  else return n*factorial(n-1);
}

int main(){
  int n;
  cin >> n;
  cout << factorial(n) << endl;
  return 0;
}

C++: //Circumscribed Circle of a Triangle

#include<iostream>
#include<cstdio>
using namespace std;

int fac(int n){
    if(n == 0 || n == 1) return 1;
    
    return (n * fac(n -1));
}

int main(void){
    int n, res;
    
    cin >> n;
    
    res = fac(n);
    
    cout << res << endl;
    
    return 0;
}

C++: #include <iostream>
using namespace std;
int main(){
    int n,i=2,t;cin>>t;n=t;
    for(;i<t;i++)n*=i;
    cout<<n<<endl;
}

C++: #include <iostream>
using namespace std;

int main()
{
 int x;
 long long int sum=1;
 while(cin>>x)
 {
 for(int i=1; i<=x; i++)
 {
 sum*=i;
 }
 cout<<sum<<endl;
}
return 0;
}

C++: #include <iostream>
int factorial(int n)
{
    if (n == 0) {
        return 1;
    } 
    else {
        return n * factorial(n-1);
    }
}
int main()
{
    int n;
    std::cin  >> n;
    std::cout << factorial(n) << std::endl;
}

C++: #include<iostream>
using namespace std;

int main() {
	int n, sum = 1;
	cin >> n;
	for (int i = 1;i <= n;i++) {
		sum = sum * i;
	}
	cout << sum << endl;

	return 0;}

C++: #include <iostream>
#include <algorithm>
#include <cstdlib>
using namespace std;

int kaijou(int);
int n;

int main(){
	cin >>n;
	cout << kaijou(n) <<endl;

	return 0;
}

int kaijou(int i){
	if(i == 0){
		return 1;
	} else {
		return i * kaijou(i-1);
	}
}

C++: #include <iostream>
#include <algorithm>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <cstring>
#include <climits>
#include <cmath>
#include <cfloat>

using namespace std;

int num;
unsigned long int fac=1;

int main()
{
	cin >> num;
	
	for( int i = 1; i <= num; i++)
	{
		fac *= i;
	}
	
	cout << fac << endl;
	
	return 0;
	
}

C++: #include <iostream>

using namespace std;

void Solution()
{
    int n;
    
    cin>>n;
    
    long sum = n;
    
    for(int i = 0; i < n; i++)
    {
        sum = sum * (n - 1);
        n--;
    }
    
    cout << sum << endl;
    
    return;
}

int main()
{
    Solution();
    return 0;
}

C++: #include <iostream>
using namespace std;
int main() {
	int n; cin >> n;
	long long fac = 1;
	while (--n) {
		fac *= (n+1);
	}
	cout << fac << endl;
}

C++: //
//  main.cpp
//  kyougi
//
//  Created by 寺林 一旭 on 2018/08/27.
//  Copyright © 2018年 寺林 一旭. All rights reserved.
//

#include <iostream>
#include <vector>
#include <algorithm>
#include <stdio.h>
#include <map>
using namespace std;
int main() {
    
    int num;
    int inputValue;
    vector<int> list;
  
    while(cin >> num) //getline(cin, num))
    {
        int ans=1;
        for( int i = 1; i <= num ; i++)
        {
            ans = ans * i;
        }
        cout << ans << endl;
      //  cout << digit << endl;
   //     cout << a-b <<endl;
    }
  
    
    return 0;
}

C++: #include <cstdio>
#include <cstring>
#include <algorithm>
#include <string>
#include <cmath>
#include <stack>
#include <vector>


using namespace std;

int main()
{
	int n;
	scanf("%d", &n);
	long long res = 1;
	for (int i = 2; i <= n; ++i)
		res *= i;
	printf("%lld\n", res);

	return 0;
}

C++: #include <iostream>

using namespace std;

int main(void) {
	int i;
	unsigned long long in;

	cin >> in;
	for(i=in;i>1;i--) {
		in*=i-1;
	}
	cout << in << endl;

	return 0;
}

C++: #include<stdio.h>
#include<iostream>
#include<math.h>
#include<algorithm>
#include<string>
#define pi 3.14159
using namespace std;

long int fact(long int n) {
	long int m;
	if(n == 1) return 1;
	else {
		m =n * fact(n - 1);
		cout << m <<endl;
	}
}

int main() {
	long int n;
	cin >> n;
	fact(n);

	

	return 0;
}

C++: #include<cstdio>
typedef long long int ll;
ll f(ll n){return n==0?1:n*f(n-1);}
int main(){
  int n;scanf("%d",&n);printf("%lld\n",f(n));
}

C++: #include <cstdio>
using namespace std;

int main()
{
	int n;
	
	scanf("%d", &n);
	long long total=1;
	
	for(int i = 2; i <= n; i++){
		total *= i;
	}
	
	printf("%d\n", total);
	
	return (0);
}

C++: #include <iostream>
#include <cmath>
#include <vector>
#include <stack>
#include <algorithm>
using namespace std;

int main () {
	int n;
	cin >> n;
	long ans = 1;
	for(int i = n; i > 0; i--){
		ans *= i;
	}
	cout << ans << endl;
}

C++: #include <iostream>
int factorial(int i)
{
  if (i <= 1) return 1;
  else        return i * factorial(i - 1);
}
int main()
{
  int n;
  std::cin >> n;
  std::cout << factorial(n) << std::endl;
  return 0;
}

C++: #include<iostream>
using namespace std;

int main()
{
    int n;
    cin >> n;

    long long int total=1;
    for(int i=1; i<=n; i++) total*=i;

    cout << total << endl;
    return 0;
}

C++: #include "bits/stdc++.h"
#include<unordered_map>
#include<unordered_set>
#pragma warning(disable:4996)
using namespace std;
using ld = long double;
template<class t>
using table = vector<vector<t>>;
const ld eps=1e-9;

//// < "d:\d_download\visual studio 2015\projects\programing_contest_c++\debug\a.txt" > "d:\d_download\visual studio 2015\projects\programing_contest_c++\debug\b.answer"
int main() {
	int N; cin >> N;
	long long int ans = 1;
	while (N) {
		ans *= N;
		N--;
	}
	cout << ans << endl;
	return 0;
}

C++: #include<iostream>
using namespace std;
int main(){
int n;

while(cin>>n){
long long pro = 1;
for(int i=1;i<=n;i++){
pro*=i;
}
cout << pro << endl;
}
return 0;
}

C++: #include<stdio.h>
int main()
{
   long long int n;
    while(scanf("%lld",&n)==1)
    {
       long long int sum=1;
        for(long long int i=n;i>0;i--)
            sum*=i;
        printf("%lld\n",sum);
    }
}

C++: #include <iostream>
using namespace std;
using ll = long long;

ll fact(ll n) {
    return n==1 ? 1 : n*fact(n-1);
}

int main() {
    int n; cin>>n;
    cout<<fact(n)<<endl;
}

C++: #include <iostream>

using namespace std;

int main()
{
    long long n,result;
    int fact = 1;
    
    cin >> n;
    
    for(int i = 1; i <= n ; i++)
    {
    fact = fact * i ;
    }
    cout << fact;
    
    return 0;
    
}

C++: #include<stdio.h>

int kaijo(int);


int main()
{
	int n;
	scanf("%d", &n);
	printf("%d\n", kaijo(n));
}

int kaijo(int n)
{
	if (n == 0)return 1;
	return n*kaijo(n - 1);
}

C++: #include <iostream>
using namespace std;

int main(void)
{
 int n;
 long long int sum;
 while(cin>>n)
 {
  for(int i=1; i<=n; i++)
 {
 sum*=i;
 }
cout<<sum<<endl;
}
return 0;
}

C++: #include <iostream>

using namespace std;

int main(){
	long double n; cin >> n;
	for(int i = n - 1; i > 1; i--)
		n *= i;
	cout << n;
	return 0;
}

C++: #include <cstdio>

int main(void)
{
	int n;
	int i;
	long sum;
	
	sum = 1;
	
	scanf("%d", &n);
	
	for (i = 1; i <= n; i++){
		sum *= i;
	}
	printf("%d\n", sum);
	
	
	return (0);
}

C++: #include <iostream>
using namespace std;

int main()
{
  int n;
  while (cin >> n) {
    unsigned long long int f = 1;
    for (int i = 2; i < n+1; ++i)
      f *= i;
    cout << f << endl;
  }
  return 0;
}

C++: #include <iostream>
#include <cstdio>
#include <cstring>
using namespace std;

int main()
{
    int n,f=1,i;
    scanf("%d",&n);
    for(i=2;i<=n;i++)
        f=f*i;
    if(n==0)
           printf("0\n");
    else
           printf("%d\n",f);
    return 0;
}