Triangle classification

Implement a program that reads three integer numbers: a, b and c. The program must indicate whether the numbers can represent the sides of a triangle. For this, each value must be less than the sum of the other two. If so, the program must indicate if it is a:

• scalene triangle (if all three sides are different),

• equilateral triangle (if all three sides are equal), or

• isosceles triangle (two equal sides and one different).

This triangle challenge is well known. It was proposed by Jerry Weinberg¹, a famous computer scientist, and described by Glenford Myers, who wrote the first book on software testing, the classic The Art of Software Testing².

Test your program with the set of test cases proposed below:

test case ID	inputs			expected output
	a	b	c
1	1	50	50	Isosceles
2	2	50	50	Isosceles
3	99	50	50	Isosceles
4	100	50	50	Not a Traingle
5	50	50	50	Equilateral
6	50	1	50	Isosceles
7	50	2	50	Isosceles
8	50	99	50	Isosceles
9	50	100	50	Not a Triangle
10	50	50	1	Isosceles
11	50	50	2	Isosceles
12	50	50	99	Isosceles
13	50	50	100	Not a Triangle

Insist that the students test their programs by giving them test
cases. Also include a bit of anecdotal history on the triangle
program and first book on software testing.

1. https://en.wikipedia.org/wiki/Gerald_Weinberg ↩

2. https://onlinelibrary.wiley.com/doi/book/10.1002/9781119202486 ↩