Fill in the Gaps

2023-01-23.py

question = """
You are given a list of positive integers which represents some range of 
integers which has been truncated. Find the missing bits, insert ellipses 
to show that that part has been truncated, and print it. 
If the consecutive values differ by exactly two, then insert 
the missing value.

Examples:

> missingBits([1,2,3,4,20,21,22,23])
> "[1,2,3,4,...,20,21,22,23]"

> missingBits([1,2,3,5,6])
> "[1,2,3,4,5,6]"

> missingBits([1,3,20,27])
> "[1,2,3,...,20,...,27]"
"""

def missingBits(arr):
    filled_arr = []
    for i in range(0,len(arr)-1):
        filled_arr.append(str(arr[i]))
        if arr[i+1] == arr[i] + 2:
            filled_arr.append(str(arr[i]+1))
        elif arr[i+1] > arr[i] + 1:
            filled_arr.append('...')
    filled_arr.append(str(arr[-1]))
    return ','.join(filled_arr)

print(missingBits([1,2,3,4,20,21,22,23]))
print(missingBits([1,2,3,5,6]))
print(missingBits([1,3,20,27]))