Python Exercise 14: sum of fractions

Question

• Create a function that takes a list containing nested lists as an argument.
• Each sublist has 2 elements.
• The first element is the numerator and the second element is the denominator.
• Return the sum of the fractions rounded to the nearest whole number.

Examples

sum_fractions([[18, 13], [4, 5]]) ➞ 2

sum_fractions([[36, 4], [22, 60]]) ➞ 9

sum_fractions([[11, 2], [3, 4], [5, 4], [21, 11], [12, 6]]) ➞ 11

My solution

• algorithm

>>separate the sublist in the nested list
  iterate over the nested list
>>separate elementes in the sublist
  iterate over the sublist
>>for each sublist, calculate the fraction
  set the first element to the numerator 
  set the second element is the denominator
  store the result to a variable called:total
>>return the variable total

• code

  def sum_fractions(nested_list:list):  
  total = 0  
  list_of_sum = list()  
  for sublist in nested_list:  
      division = int(sublist[0]) / int(sublist [1])  
      total += division  
  return round(total)  

  Other solution

• unpacking the sublist by multiple assignment
  • i.e. use numerator for the first element of the sublist
    • use denominator for the second element of the sublist

def sum_fractions(lst):
    return round(sum(numerator/ denominator for numerator, denominator in lst))

My reflection

• I have learned using multiple assignment instead of using index to access the value of a list.

Credit

• challenge find on edabit