Problem with a small code

Question

Hello , Can anyone plz tell me how do i get this output from this sample code ? im new to java...
public class Fact2
int factorial (int n) {
int res;
System.out.println(n);
if (n == 1) return 1;
res = factorial (n - 1) * n ;
System.out.println("res " + res);
return res;
public static void main (String [] args) {
Fact2 f= new Fact2();
System.out.println("The factorial of this number is " + f.factorial(5));
The output is :
C:\Documents and Settings\AM>java Fact2
5
4
3
2
1
res 2
res 6
res 24
res 120
The factorial of this number is 120
Here , from 5 to 1 is understood and also the last phrase of course , but from where did the variable "res" have these values 2,6,24 ....

Answer 1

2: int factorial (int n) {
3: int res;
4: System.out.println(n);
5: if (n == 1) return 1;
6: res = factorial (n - 1) * n ;
7: System.out.println("res " + res);
8: return res;
9: }
When you call factorial(5) this will happen:
It prints 5 (line 4)
It calls factorial(4) (line 6) - (and waits for it result!!!!!)
factorial(4) shall print 4, and calls factorial(3)
prints 3, calls factorial(2)
prints 2, calls factorial(1)
prints 1, returns 1returns from factorial(1), multiplies it by 2 (line 6), result = 2
prints the result to the screen (line 7)
returns the result (line 8) (thus 2)multiplies the result of factorial(2) with 3 (line 6), result = 6
prints this result, and returns itmultiplies the result of factorial(3) with 4, result = 24
prints this result, and returns itmultiplies the result of factorial(4) with 5, result = 120
prints this result and returns itHope this get things clear to you