loop problems

// factorial with loop

import java.util.*;
import java.lang.*;
import java.io.*;

public class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
      Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      long fact = 1;
      for(int i=1;i<=n;i++){
        fact = fact*i;
      }
      System.out.println(fact);
	}
}


    /// ARMSTRONG NUMBER 
import java.util.*;

public class Main
{
	public static void main (String[] args) throws java.lang.Exception
  {
    int j;
      for(j=1;j<=500;j++){
        int temp=j;
        int r;
      int sum=0;
      while(temp>0){
        r = temp%10;
        sum = sum+(r*r*r);
        temp =temp/10;
      }
       if(sum==j){
         System.out.println(j);
         
       } 
       
     }
  }
       
       // REVERSE A DIGIT
       import java.util.*;
import java.lang.*;
import java.io.*;

public class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner sc = new Scanner(System.in);
      long n =sc.nextLong();
      long rem;
      int i=1;
      long sum=0;
      while(n>0){
        rem = n%10;
        sum = sum*10+rem;
        n=n/10;
        i++;
      }
      System.out.println(sum);
	   
    }
  }
          // POWER OF A NUMBER
          import java.util.*;
import java.lang.*;
import java.io.*;

public class Main
{
	public static void main (String[] args) throws java.lang.Exception
	{
		Scanner sc = new Scanner(System.in);
      int n = sc.nextInt();
      int p =sc.nextInt();
      int pow =1;
      while(p!=0){
        pow =pow*n;
        --p;
      }
      System.out.println(pow);
     /*for(int i=1;i<=p;i++){
        pow = pow *n;
     } 
      System.out.println(pow);*/
	}
}