Assignment 7.
Problem
Construct a weakly robust equivalence class test case for the following triangle problem.
Triangle problem: Enter three positive integers not exceeding 100 as the three sides of the triangle, and determine whether the triangle is an equilateral triangle, an isosceles scalene triangle, a complete scalene triangle, or not a triangle.
Divide equivalence classes
The three sides of the triangle are marked S = { a , b , c } S=\{a,b,c\}S={ a,b,c } , then the equivalence classes of weak robustness are divided as follows
（1） S ⊆ N ∗ S \subseteq \N^{*} S⊆N∗
（2） S ⊆ Z − N ∗ S \subseteq \Z - \N^{*} S⊆WITH−N∗
（3） ∀ s ∈ S , s ∈ [ 1 , 100 ] \forall s \in S,s\in[1,100] ∀s∈S,s∈[1,100]
（4） ∃ s ∈ S , s ∈ ( − ∞ , 1 ) ∪ ( 100 , + ∞ ) \exist s \in S, s \in (-\infty,1) \cup (100, +\infty) ∃s∈S,s∈(−∞,1)∪(100,+∞)
（5） a = b = c a=b=c a=b=c
（6） ∃ x 1 ∈ S , ∃ x 2 ∈ S − { x 1 } , x 3 ∈ S − { x 1 , x 2 } , ( x 1 ≠ x 3 ) ∧ ( x 1 = x 2 ) \exist \ x_1 \in S, \ \exist x_2 \in S-\{x_1\}, x_3 \in S-\{x_1, x_2\},(x_1 \neq x_3) \wedge (x_1=x_2) ∃x 1∈S, ∃x2∈S−{ x1},x3∈S−{ x1,x2},(x1̸=x3)∧(x1=x2)
（7） a ≠ b ≠ c a \neq b \neq c a̸=b̸=c
（8） ( a + b < = c ) ∨ ( a + c < = b ) ∨ ( b + c < = a ) (a+b<=c) \vee (a+c<=b) \vee (b+c<=a) (a+b<=c)∨(a+c<=b)∨(b+c<=a)
| input condition | Effective Equivalence Class | invalid equivalence class |
|---|---|---|
| input as positive integer | （1） | （2） |
| Enter a value that does not exceed 100 | （3） | （1） |
| Equilateral triangle | （5） | （6），（7），（8） |
| isosceles scalene triangle | （6） | （5），（7），（8） |
| complete scalene triangle | （7） | （5），（6），（8） |
| cannot form a triangle | （8） | （5），（6），（7） |
Create test cases
| Test Case | a | b | c | Expected Output |
|---|---|---|---|---|
| WN1 | 5 | 5 | 5 | Equilateral |
| WN2 | 5 | 5 | 4 | Isosceles |
| WN3 | 3 | 4 | 5 | Scalene |
| WN4 | 1 | 1 | 2 | Not a triangle |
| WR5 | -1 | 5 | 5 | Value of a is out of range |
| WR6 | 5 | -1 | 5 | Value of b is out of range |
| WR7 | 5 | 5 | -1 | Value of c is out of range |
| WR8 | 101 | 5 | 5 | Value of a is out of range |
| WR9 | 5 | 101 | 5 | Value of b is out of range |
| WR10 | 5 | 5 | 101 | Value of c is out of range |
| WR11 | 5.1 | 5 | 5 | Value of a is not int |
| WR12 | 5 | 5.1 | 5 | Value of b is not int |
| WR13 | 5 | 5 | 5.1 | Value of c is not int |