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Solution Notebook

Problem: Implement foo(val), which returns val

Constraints
Test Cases
Algorithm
Code
Unit Test

Constraints

Does foo do anything else?
- No

Test Cases

foo(val) -> val

Algorithm

Return the input, val

Complexity:

Time: O(1)
Space: O(1)

Code



In [1]:

    
def foo(val):
    return val

Unit Test



In [2]:

    
%%writefile test_foo.py
from nose.tools import assert_equal


class TestFoo(object):

    def test_foo(self):
        assert_equal(foo(None), None)
        assert_equal(foo(0), 0)
        assert_equal(foo('bar'), 'bar')
        print('Success: test_foo')

        
def main():
    test = TestFoo()
    test.test_foo()

    
if __name__ == '__main__':
    main()









    



Overwriting test_foo.py



In [3]:

    
%run -i test_foo.py









    



Success: test_foo