Go: package main

import "fmt"

func main() {
	var n int
	fmt.Scan(&n)

	rs := 1
	for i := 1; i <= n; i++ {
		rs *= i
	}
	fmt.Println(rs)
}

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

int main(){
    
    cin >> c;
    int ans = c;
    for(;c > 0;){
        
        if(c-1 != 0){
              ans = ans *(c-1);
             }
       
        
        c--;
          }
          
          cout << ans;
    system("pause");
    return 0;
    }

C++: #include <iostream>
#include <cstdio>

using namespace std;

int main(void)
{
	int a;
	long long int c;
	while(cin>>a)
	{
		c=a;
		while(a!=1)c*=--a;
		cout<<c<<endl;
	}
	return 0;
}

C++: #include<cstring>
#include<cstdio>
#include<iostream>

using namespace std;


int main(){
int n, ans=1;

cin >> n;

while(n>1)	ans*=n--;

cout << ans << endl;

	return 0;
}

C++: #include <stdio.h>

int main(){
	int n;
	int x[40];
	int i,k;
	int Flag = 0;
	
	for(i = 0;i < 40;i++){
		x[i] = 0;
	}
	
	x[39] = 1;
	
	scanf("%d",&n);
	
	for(i = 1;i <= n;i++){
		for(k = 0;k <= 39;k++){
			x[k] *= i;
		}
		
		for(k = 39;k >= 0;k--){
			if(x[k] >= 10){
				x[k-1] += x[k]/10;
				x[k] %= 10;
			}
		}
	}
	
	for(i = 0;i < 40;i++){
		if(x[i] != 0){
			Flag = 1;
		}
		if(Flag == 1){
			printf("%d",x[i]);
		}
	}
	
	printf("\n");
	
	return 0;
}

C++: //Circumscribed Circle of a Triangle

#include<iostream>
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>
#include<string>
#include<algorithm>
#include<map>
#include<set>
#include<utility>
#include<vector>
#include<cmath>
#include<cstring>
#include<cstdio>
#define loop(i,a,b) for(int i=a;i<b;i++) 
#define rep(i,a) loop(i,0,a)
#define rp(a) while(a--)
#define pb push_back
#define mp make_pair
#define all(in) in.begin(),in.end()
const double PI=acos(-1);
const double EPS=1e-10;
using namespace std;
typedef long long ll;
typedef vector<int> vi;
int main(){
	int n;
	ll out=1;
	cin>>n;
	rep(i,n)out*=i+1;
	cout<<out<<endl;
}

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

long long ans = 1;

int Factional(int n){
  if(n == 1)return 1;
  else{
    return ans = n * Factional(n - 1);
  }
}

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

C++: #include <iostream>

using namespace std;

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

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

	cout << f << endl;

	return 0;
}

C++: #include <stdio.h>
#include <iostream>

int main(){
    long long num, factorial=1;
   scanf("%lld", &num);
    for(;num > 0; num--){
        factorial *= num;
    }
printf("%lld", factorial);
    return 0;
}

C++: #include <iostream>
using namespace std;
 
int main()
{
int n;
long f=1;
cin>>n;
for(int i=1;i<=n;i++)
f=f*i;
cout<<f;
return 0;
}

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

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

C++: #include<stdio.h>
#include<string.h>
int main()
{
    int a,ans;
    double p;
    while(scanf("%d",&ans)==1)
    {
        p=1;
        for(a=2;a<=ans;a++)
            p = p*a;
        printf("%0.lf\n",p);
    }
}

C++: #include <cstdio>

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

int main(){
	int a;
	scanf("%d", &a);
	printf("%ld\n", fact(a));
	return 0;
}

C++: #include<cstdio>
#include<iostream>

using namespace std;

int main(){
    long long k=1;
    for(int i=1;i<=20;i++){
        k*=i;
    }
    cout<<k<<endl;
        return 0;
}

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

}

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

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

C++: #include <iostream>
#include <string>
#include <algorithm>
#include <utility>
#include <iomanip>
#include <functional>
#include <queue>
#include <stack>
#include <cmath>
#define INF 100000000
#define MOD 1000000007
using namespace std;


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

C++: #include <iostream>
#include <algorithm>
#include <functional>

using namespace std;

int main(int argc, char const* argv[])
{
	unsigned int n;
	int i;

	cin >> n;

	for( i = n,n = 1;i >= 1;i-- ) n *= i;

	cout << n << endl;

	return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

typedef long long ll;

#define FOR(i,a,b) for(int i=(a);i<(b);i++)
#define REP(i,a) FOR(i,0,a)

int main(){
	int n;
	cin>>n;
	ll fact=1;
	FOR(i,2,n+1){
		fact*=i;
	}
	cout<<fact<<endl;
	return 0;
}

C++: 
#include <iostream>
using namespace std;
int main(){
    int n,i,ans[20];
    cin>>n;
    for(i=0;i<=n;i++){
        if(i==0){
            ans[0]=1;
        }else{
            ans[i]=ans[i-1]*i;
        }
    }
    cout<<ans[n]<<endl;
    return 0;
}

C++: #include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <math.h>
#include <numeric>

using namespace std;

long long int a(long long int x) {
	if (x == 1) {
		return 1;
	}
	return x * a(x - 1);
}

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

C++: #include <iostream>
#include<algorithm>
using namespace std;
int main(){
    long long n,ans=1;
    cin>>n;
    for(int i=1;i<=n;i++){
        ans*=i;
    }
    cout<<ans<<endl;
    return 0;
}

C++: #include <stdio.h>

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

C++: #include <iostream>

using namespace std;

int main(){
	long long int list[21];
	list[0]=1;
	int n;
	cin >> n;
	for(int i=1;i<=n;i++)
		list[i]=list[i-1]*i;
	cout << list[n] << endl;
	return 0;
}

C++: #include <iostream>
#include <vector>
#include <string>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <algorithm>	// require sort next_permutation count __gcd reverse etc.
#include <cstdlib>	// require abs exit atof atoi 
#include <cstdio>		// require scanf printf
#include <functional>
#include <numeric>	// require accumulate
#include <cmath>		// require fabs
#include <climits>
#include <limits>
#include <cfloat>
#include <iomanip>	// require setw
#include <sstream>	// require stringstream 
#include <cstring>	// require memset
#include <cctype>		// require tolower, toupper
#include <fstream>	// require freopen
#include <ctime>		// require srand
#define rep(i,n) for(int i=0;i<(n);i++)
#define ALL(A) A.begin(), A.end()

using namespace std;

typedef long long ll;
typedef pair<int, int> P;
ll f[22];

int main()
{
//	cut here before submit 
//	freopen ("testcase.dat", "r", stdin );
	memset (f, 0LL, sizeof (f ) );
	f[0] = 1LL;
	f[1] = 1LL;
	for (int i = 2; i <= 20; i++ ){
		f[i] = (ll)i*f[i-1];
	} // end for
/*
	rep (i, 21 ){
		cout << f[i] << endl;
	} // end rep
*/
	string str = "";
	while (getline (cin, str ) ){
		stringstream ss (str );
		int n;
		ss >> n;
		cout << f[n] << endl;
	} // end loop
		
	return 0;
}

C++: #include <iostream>

unsigned fact(unsigned int n)
{
    if (n <= 1) return 1;
    else return n * fact(n - 1);
}

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

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

int main()
{
	long long int ans = 1;
	int n;

	cin >> n;
	for (int i = 1; i <= n; i++) ans *= i;
	cout << ans << endl;

	return 0;
}