What will be the output of the following code..?Also plz include steps in your answer...

Question

#include <iostream>
void e(int) ;
int main()
{ int a=3;
e(a);
return 0;
}
void e(int n)
{
if(n>0)
{
e(--n);
cout <<n;
e(--n);
}
}

Answer 1

Your 'extra' zero is display 7 lines from bottom because n was high enough for the line 16 call to actually enter it's if.

Answer 2

A compiler error as e is undefined where you call it in main.

Answer 3

Thanks John Wells ...

Answer 4

I have edited my code
John Wells...

Answer 5

https://code.sololearn.com/chUjMWi5PoQf/?ref=app

Answer 6

Line 8 calls e with 3.
Line 14 is true (nested e level 1).
Line 16 changes n to 2 and calls e with 2 (1).
Line 14 is true (2).
Line 16 changes n to 1 and calls e with 1 (2).
Line 14 is true (3).
Line 16 changes n to 0 and calls e with 0 (3).
Line 14 is false (4).
Line 20 exits e (4).
Line 17 displays 0 (3).
Line 18 changes n to -1 and calls e with -1 (3).
Line 14 is false (new 4).
Line 20 exits e (4).
Line 20 exits e (3).
Line 17 displays 1 (2).
Line 18 changes n to 0 and calls e with 0 (2).
Line 14 is false (new 3).
Line 20 exits e (3).
Line 20 exits e (2).
Line 17 displays 2 (1).
Line 18 changes n to 1 and calls e with 1 (1).
Line 14 is true (new 2).
Line 16 changes n to 0 and calls e with 0 (2).
Line 14 is false (new 3).
Line 20 exits e (3).
Line 17 displays 0 (2).
Line 18 changes n to -1 and calls e with -1 (2).
Line 14 is false (new 3).
Line 20 exits e (3).
Line 20 exits e (2).
Line 20 exits e (1).
Line 10 exits program