Challenge 09: Seb's Horchata Hustle

Despite securing employment at the international fruit farm, Seb is not quite done hustling yet. In between sigma grinding this summer, surveilling peers and colleagues on social media, and experimenting with advanced emoji generation algorithms, Seb has decided to setup a booth selling fresh horchata¹!

An enterprising fellow, Seb decides to sell each delicious cup of rice milk with cinnamon at reasonable price of $5². Moreover to keep things simple, he only will accept bills in the following denominations: $5, $10, and $20.

Unfortunately, his small business is a bit underresourced, so he doesn't have any capital left after making his batch of horchata. This means that if any customer requires change (ie. pays $10 or $20 instead of $5), he must make change out of the money he has already collected from previous customers... which is quite the challenge in this economy and highly dependent on the sequence of customers.

For instance, given the following sequence of customers, represented by the bills they are using to pay for their horchata:

5 5 5 10 20

The first three customers don't need any change because they paid the exact amount for a cup of horchata. The fourth customer requires $5 which is fine since you have 3 of those bills. The fifth customer requires $15 which is also fine since you can give them the $10 and one of your remaining $5. So in this sequence, Seb can successfully provide each customer the exact amount of change they each required.

However, given the following sequence of customers

5 5 10 10 20

The first two customers don't need any change because they paid the exact amount of a cup of horchata. The third customer requires $5 which is fine since you have two of those bills. Likewise, the fourth customer also requires $5 in change which is okay since you have one left. Unfortunately, the last customer, requires $15 in change, but you can't do this since you only have two $10 bills left and thus cannot make exact change for each customer.

Because of this volatility and to determine if this business model is even feasible, Seb wants to write a simulator that takes in a sequence of customers (represented by the dollar bills they are spending) and determines whether or not he can give each customer the correct amount of change despite starting the business with 0 money.

Unfortunately, he is busy doing hero office hours late at night in the library again and needs you to write the simulator for him.

Input¶

You will be given a series of input test cases. Each input test case is a sequence of customers and the bills (ie. 5, 10, or 20) they are using to pay for their horchata.

Example Input¶

5 5 5 10 20
5 5 10 10 20

Output¶

For each input test case, output Yeah if Seb can provide every customer in the sequence the correct amount of change. Otherwise, output Nope.

Prefix each output with the test case number, starting with 1.

Example Output¶

Here is the output for the example input above:

1. Yeah
2. Nope

Submission¶

To submit your work, follow the same procedure you used for Reading 01:

$ cd path/to/cse-30872-su24-assignments     # Go to assignments repository
$ git checkout master                       # Make sure we are on master
$ git pull --rebase                         # Pull any changes from GitHub

$ git checkout -b challenge09               # Create and checkout challenge09 branch

$ $EDITOR challenge09/program.cpp           # Edit your code

$ git add challenge09/program.cpp           # Stage your changes
$ git commit -m "challenge09: done"         # Commit your changes

$ git push -u origin challenge09            # Send changes to GitHub

To check your code, you can use the .scripts/check.py script or curl:

$ .scripts/check.py
Checking challenge09 program.c ...
  Result Success
    Time 0.00
   Score 6.00 / 6.00

$ curl -F source=@challenge09/program.cpp https://dredd.h4x0r.space/code/cse-30872-su24/challenge09
{"result": "Success", "score": 6, "time": 0.0033686161041259766, "value": 6, "status": 0}