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to Kindergarten Garden in the Python Track

Published at Jul 21 2018 · 0 comments
Instructions
Test suite
Solution

Note:

This exercise has changed since this solution was written.

Given a diagram, determine which plants each child in the kindergarten class is responsible for.

The kindergarten class is learning about growing plants. The teacher thought it would be a good idea to give them actual seeds, plant them in actual dirt, and grow actual plants.

They've chosen to grow grass, clover, radishes, and violets.

To this end, the children have put little cups along the window sills, and planted one type of plant in each cup, choosing randomly from the available types of seeds.

[window][window][window]
........................ # each dot represents a cup
........................

There are 12 children in the class:

  • Alice, Bob, Charlie, David,
  • Eve, Fred, Ginny, Harriet,
  • Ileana, Joseph, Kincaid, and Larry.

Each child gets 4 cups, two on each row. Their teacher assigns cups to the children alphabetically by their names.

The following diagram represents Alice's plants:

[window][window][window]
VR......................
RG......................

In the first row, nearest the windows, she has a violet and a radish. In the second row she has a radish and some grass.

Your program will be given the plants from left-to-right starting with the row nearest the windows. From this, it should be able to determine which plants belong to each student.

For example, if it's told that the garden looks like so:

[window][window][window]
VRCGVVRVCGGCCGVRGCVCGCGV
VRCCCGCRRGVCGCRVVCVGCGCV

Then if asked for Alice's plants, it should provide:

  • Violets, radishes, violets, radishes

While asking for Bob's plants would yield:

  • Clover, grass, clover, clover

Exception messages

Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include a message.

To raise a message with an exception, just write it as an argument to the exception type. For example, instead of raise Exception, you should write:

raise Exception("Meaningful message indicating the source of the error")

Running the tests

To run the tests, run the appropriate command below (why they are different):

  • Python 2.7: py.test kindergarten_garden_test.py
  • Python 3.4+: pytest kindergarten_garden_test.py

Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version): python -m pytest kindergarten_garden_test.py

Common pytest options

  • -v : enable verbose output
  • -x : stop running tests on first failure
  • --ff : run failures from previous test before running other test cases

For other options, see python -m pytest -h

Submitting Exercises

Note that, when trying to submit an exercise, make sure the solution is in the $EXERCISM_WORKSPACE/python/kindergarten-garden directory.

You can find your Exercism workspace by running exercism debug and looking for the line that starts with Workspace.

For more detailed information about running tests, code style and linting, please see Running the Tests.

Source

Random musings during airplane trip. http://jumpstartlab.com

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.

kindergarten_garden_test.py

import unittest

from kindergarten_garden import Garden


# Tests adapted from `problem-specifications//canonical-data.json` @ v1.1.0

class KindergartenGardenTest(unittest.TestCase):
    def test_garden_with_single_student(self):
        self.assertEqual(
            Garden("RC\nGG").plants("Alice"),
            "Radishes Clover Grass Grass".split())

    def test_different_garden_with_single_student(self):
        self.assertEqual(
            Garden("VC\nRC").plants("Alice"),
            "Violets Clover Radishes Clover".split())

    def test_garden_with_two_students(self):
        garden = Garden("VVCG\nVVRC")
        self.assertEqual(
            garden.plants("Bob"), "Clover Grass Radishes Clover".split())

    def test_multiple_students_for_the_same_garden_with_three_students(self):
        garden = Garden("VVCCGG\nVVCCGG")
        self.assertEqual(garden.plants("Bob"), ["Clover"] * 4)
        self.assertEqual(garden.plants("Charlie"), ["Grass"] * 4)

    def test_full_garden(self):
        garden = Garden("VRCGVVRVCGGCCGVRGCVCGCGV\nVRCCCGCRRGVCGCRVVCVGCGCV")
        self.assertEqual(
            garden.plants("Alice"),
            "Violets Radishes Violets Radishes".split())
        self.assertEqual(
            garden.plants("Bob"), "Clover Grass Clover Clover".split())
        self.assertEqual(
            garden.plants("Kincaid"), "Grass Clover Clover Grass".split())
        self.assertEqual(
            garden.plants("Larry"), "Grass Violets Clover Violets".split())

    # Additional tests for this track
    def test_disordered_test(self):
        garden = Garden(
            "VCRRGVRG\nRVGCCGCV",
            students="Samantha Patricia Xander Roger".split())
        self.assertEqual(
            garden.plants("Patricia"),
            "Violets Clover Radishes Violets".split())
        self.assertEqual(
            garden.plants("Xander"), "Radishes Grass Clover Violets".split())


if __name__ == '__main__':
    unittest.main()
# laaaazy

DEFAULT_STUDENTS = [
    'Alice',
    'Bob',
    'Charlie',
    'David',
    'Eve',
    'Fred',
    'Ginny',
    'Harriet',
    'Ileana',
    'Joseph',
    'Kincaid',
    'Larry'
]

class Garden(object):

    @staticmethod
    def plant_type(value):
        if value == 'G':
            return 'Grass'
        elif value == 'C':
            return 'Clover'
        elif value == 'R':
            return 'Radishes'
        elif value == 'V':
            return 'Violets'
        else:
            raise ValueError('Plant %s is unknown', value)

    def __init__(self, diagram, students=DEFAULT_STUDENTS):
        garden_rows = diagram.split('\n')
        self.garden = [list(row) for row in garden_rows]
        self.students = sorted(students)
        self.class_size = len(students)

    def get_garden_idx(self, student):
        if student in self.students:
            student_idx = self.students.index(student)
            start_idx = student_idx * 2
            end_idx = start_idx + 2
        else:
            raise ValueError('Student %s is not in this class', student)

        return (start_idx, end_idx)

    def plants(self, student):
        plant_values = []
        if student in self.students:
            i, j = self.get_garden_idx(student)
            for row in self.garden:
                plant_values.extend(row[i:j])
        else:
            raise ValueError('Student %s is not in this class', student)

        return [Garden.plant_type(value) for value in plant_values]

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