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Python Data Structures and Algorithms - Recursion: Sum of n+(n-2)+(n-4)...

Python Recursion : Exercise-7 with Solution

Write a Python program to calculate the sum of the positive integers of n+(n-2)+(n-4)... (until n-x =< 0).

Sample Solution:

Python Code:

def sum_series(n):
  if n < 1:
    return 0
  else:
    return n + sum_series(n - 2)

print(sum_series(6))
print(sum_series(10))

Sample Output:

12                                                                                                            
30

Flowchart:

Flowchart: Recursion: Sum of  n+(n-2)+(n-4)....

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Previous: Write a Python program to get the sum of a non-negative integer.
Next: Write a Python program to calculate the harmonic sum of n-1.

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Python: Tips of the Day

Decapitalizes the first letter of a string:

Example:

def tips_decapitalize(s, upper_rest=False):
  return s[:1].lower() + (s[1:].upper() if upper_rest else s[1:])
print(tips_decapitalize('PythonTips'))
print(tips_decapitalize('PythonTips', True)) 

Output:

pythonTips
pYTHONTIPS