Project Solution

Remember you will only modify the les addition.py, buyLotsOfFruit.py, and shopSmart.py that were provided.




Question 1: Addition




Open addition.py and look at the de nition of add:




def add(a, b):




"Return the sum of a and b"




"*** YOUR CODE HERE ***"




return 0




The tests called this with a and b set to di erent values, but the code always returned zero. Modify this de nition to read:




def add(a, b):




"Return the sum of a and b"




print "Passed a=%s and b=%s, returning a+b=%s" % (a,b,a+b)




return a+b




Now rerun the autograder (omitting the results for questions 2 and 3):




cs325/p0$ python autograder.py




Starting on 1-21 at 23:52:05




Question q1




===========




Passed a=1 and b=1, returning a+b=2




PASS: test_cases/q1/addition1.test



add(a,b) returns the sum of a and b Passed a=2 and b=3, returning a+b=5



PASS: test_cases/q1/addition2.test



add(a,b) returns the sum of a and b Passed a=10 and b=-2.1, returning a+b=7.9



PASS: test_cases/q1/addition3.test



add(a,b) returns the sum of a and b



### Question q1: 1/1 ###




...




Finished at 23:41:01




Provisional grades




==================




Question q1: 1/1




Question q2: 0/1




Question q3: 0/1




------------------




Total: 1/3




...



You now pass all tests, getting full marks for question 1. Notice the new lines "Passed a=..." which appear before "*** PASS: ...". These are produced by the print statement in add. You can use print statements like that to output information useful for debugging. You can also run the autograder with the option --mute to temporarily hide such lines, as follows:




Question q1




===========




PASS: test_cases/q1/addition1.test



add(a,b) returns the sum of a and b



PASS: test_cases/q1/addition2.test



add(a,b) returns the sum of a and b



PASS: test_cases/q1/addition3.test



add(a,b) returns the sum of a and b



### Question q1: 1/1 ###




...




Question 2: buyLotsOfFruit Function




Add a buyLotsOfFruit(orderList) function to buyLotsOfFruit.py which takes a list of (fruit,pound) tuples and returns the cost of your list. If there is some fruit in the list which doesn’t appear in fruitPrices it should print an error message and return None. Please do not change the fruitPrices variable.




Run python autograder.py until question 2 passes all tests and you get full marks. Each test will con rm that buyLotsOfFruit(orderList) returns the correct answer given various possible inputs. For example, test_cases/q2/food_price1.test tests whether:




Cost of [(’apples’, 2.0), (’pears’, 3.0), (’limes’, 4.0)] is 12.25




Question 3: shopSmart function




Fill in the function shopSmart(orders,shops) in shopSmart.py, which takes an orderList (like the kind passed in to FruitShop.getPriceOfOrder) and a list of FruitShop and returns the FruitShop where your order costs the least amount in total. Don’t change the le name or variable names, please. Note that we will provide the shop.py implementation as a "support" le, so you don’t need to submit yours.




Run python autograder.py until question 3 passes all tests and you get full marks. Each test will con rm that shopSmart(orders,shops) returns the correct answer given various possible inputs. For example, with the following variable de nitions:




orders1 = [(’apples’,1.0), (’oranges’,3.0)]




orders2 = [(’apples’,3.0)]




dir1 = {’apples’: 2.0, ’oranges’:1.0}




shop1 = shop.FruitShop(’shop1’,dir1)




dir2 = {’apples’: 1.0, ’oranges’: 5.0}




shop2 = shop.FruitShop(’shop2’,dir2)




shops = [shop1, shop2]




test_cases/q3/select_shop1.test tests whether:




shopSmart.shopSmart(orders1, shops) == shop1




and test_cases/q3/select_shop2.test tests whether:




shopSmart.shopSmart(orders2, shops) == shop2