What Type of Triangle?

Create a function which returns the type of triangle, given the side lengths. Return the following values if they match the criteria.

• No sides equal: "scalene"
• Two sides equal: "isosceles"
• All sides equal: "equilateral"
• Less or more than 3 sides given: "not a triangle"

Examples

getTriangleType([2, 6, 5]) ➞ "scalene"

getTriangleType([4, 4, 7]) ➞ "isosceles"

getTriangleType([8, 8, 8]) ➞ "equilateral"

getTriangleType([3, 5, 5, 2]) ➞ "not a triangle"

Notes

• You will be given an array of positive integers.