Range of Numbers

Create a function that takes a list of integers and returns the range of consecutive numbers separated by dash a - between starting and ending numbers.

• Separate different ranges by , commas.
• A range of numbers will be considered if three or more consecutive numbers are found in the list (see example #1).

Examples

numbers_range([-6, -3, -2, -1, 0, 1, 7, 8, 9, 10, 11, 14, 15]) ➞ "-6,-3-1,7-11,14,15"
# -6 is an alone integer.
# -3 to 1 is a range of consecutive numbers.
# 7 to 11 is a range of consecutive numbers.
# 14 and 15 are consecutive numbers but cannot be considered as a range.

numbers_range([-3, -2, -1, 2, 10, 15, 16, 18, 19, 20]) ➞ "-3--1,2,10,15,16,18-20"

numbers_range([1, 2, 3, 9, 10, 15, 16, 18, 56, 57]) ➞ "1-3,9,10,15,16,18,56,57"

Notes

N/A