+19

https://code.sololearn.com/cJkdYh5OKjEX/?ref=app Output : 0120 How???

9/3/2019 2:21:33 PM

Ayushi Gujarati

+6

Let function test ==T All test where n<=0 will return to main without printing anything T(3) / | \ / 2 \ T(2) |. T(1) /|\ |. /|\ T(1) 1 T(0) |.T(0) 0 T(-1) /|\ \. |. |. T(0)0T(-1)\. |. |. |. |. |. |. |. |. |. |. 0 1 2 0

+47

+21

Let's handtrace the steps: test( 3 ) is called x > 0 -> true test( 2 ) is called x > 0 -> true test( 1 ) is called x > 0 -> true test( 0 ) is called x > 0 -> false Nothing happens inside test( 0 ), so now we return to its caller, test( 1). Since x = 1 was decremented inside test( 1 ), x is now 0, which is then printed. Afterwards test( --0 ) <=> test( -1 ) is called. x > 0 -> false Here test( 1 ) finishes and we return to test( 2 ). Same principle, x was decremented, so now in test( 2 ), x = 1, which is printed. Then test ( 0 ) is called, without consequence, since the condition fails. Returning to test( 3 ), 2 is printed, and test( 1 ) is called, which prints 0 as we know from earlier. Afterwards, test( 3 ) is complete, hence the entire function call is resolved. Finally, putting things together, we get 0 1 2 0 as the output. If my answer didn't help, try drawing yourself a sketch on paper to visualize the function calls.

+11