public static void printfac(int n) { // after making a class we have ti make a function with condition

if (n<0){

System.out.println("invalid number");

return;

}

int factorial = 1 ;

for(int i = n; i >=1 ; i--){ // this is loop mean the condiion

factorial = factorial*i;

}

System.out.println("your factorial is ::" + factorial);

return ;

}

public static void main(String args[]){ // this is the call function we call the above function after giving the input

// to the computer

Scanner chayan = new Scanner(System.in);

int n = chayan.nextInt();

printfac(n);

}