recursion function (python beginner)

[everafter]

hi all,

need help for the code below

def tri_recursion(k):
  if(k>0): 
    result = k+tri_recursion(k-1)
    print(result)
  else:
    result = 0
  return result

print("\n\nRecursion Example Results")
tri_recursion(6)

Output:
Recursion Example Results
1 
3
6
10
15
21

how does python compute the above code?
how did k becomes greater than 0?


as per my understanding
if (k>0) then it should jump on else statement

[buran]

as per my understanding
if (k>0)then it should jump on else statement

exactly the opposite - in this case it will execute lines 3-4

on line 10 you call your function and initial value of k is 6

you can visualise step-by-step execution here

[everafter]

on line 10 you call your function and initial value of k is 6

oh that make sense to me, I thought tri_recursion(6) is the number times it will recur because I tried these steps, I changed 6 to 9 and the result is:
tri_recursion(6) #result has 6 lines
tri_recursion(9) #result has 9 lines

[buran]

I thought tri_recursion(6) is the number times it will recur

actually that is also true (in this particular case, because you sum every number, i.e. on line 3 you change k by 1 when call tri_recursion(k-1)) - on line 4 you print intermediate results as well as the final one.

if you change your code

def tri_recursion(k):
  if(k>0): 
    result = k+tri_recursion(k-2) #NOTE THE DIFF HERE
    print(result)
  else:
    result = 0
  return result
 
print("\n\nRecursion Example Results")
tri_recursion(6)

Output:
Recursion Example Results
2
6
12
>>>