Closed test cases in the activity challenge

Question

Why is some of the test cases closed?

Answer 1

ghanem altamimi in "Code Coaches" every problem is enclosed with hidden cases so it's interesting to solve those challenges without any hint as if they are open to see you can easily crack the challenge by using switch cases or if else condition so they are hidden to make the things works interesting

Answer 2

DishaAhuja So you mean even if i fulfilled the requirements of the code coaches I'd still not pass the test because there is a more preferable way to solve the problem such as if else or switch cases?

Answer 3

If all test cases were open, you would be able to pass all cases without actually solving the problem. Knowing everything that goes in and out, you would easily write a code that goes:
inp = input()
if inp == "a":
print("b")
elif inp == "c":
print("d")
...
and get all the right outputs without even bothering to solve the problem.