path: root/data_structures_and_algorithms/temperature-tracker.py

import unittest


################################################################################
# Solution
################################################################################
class TempTracker(object):
    def __init__(self):
        # min / max
        self.min = None
        self.max = None
        # mean
        self.sum = 0
        self.num = 0
        # mode
        self.nums = [0] * 111
        self.mode_num = 0
        self.mode = None

    def insert(self, x):
        # min / max
        if not self.min or x < self.min:
            self.min = x
        if not self.max or x > self.max:
            self.max = x
        # mean
        self.sum += x
        self.num += 1
        # mode
        self.nums[x] += 1
        if self.nums[x] >= self.mode_num:
            self.mode_num = self.nums[x]
            self.mode = x

    def get_max(self):
        return self.max

    def get_min(self):
        return self.min

    def get_mean(self):
        return self.sum / self.num

    def get_mode(self):
        return self.mode


# Tests


class Test(unittest.TestCase):
    def test_tracker_usage(self):
        tracker = TempTracker()

        tracker.insert(50)
        msg = 'failed on first temp recorded'
        self.assertEqual(tracker.get_max(), 50, msg='max ' + msg)
        self.assertEqual(tracker.get_min(), 50, msg='min ' + msg)
        self.assertEqual(tracker.get_mean(), 50.0, msg='mean ' + msg)
        self.assertEqual(tracker.get_mode(), 50, msg='mode ' + msg)

        tracker.insert(80)
        msg = 'failed on higher temp recorded'
        self.assertEqual(tracker.get_max(), 80, msg='max ' + msg)
        self.assertEqual(tracker.get_min(), 50, msg='min ' + msg)
        self.assertEqual(tracker.get_mean(), 65.0, msg='mean ' + msg)
        self.assertIn(tracker.get_mode(), [50, 80], msg='mode ' + msg)

        tracker.insert(80)
        msg = 'failed on third temp recorded'
        self.assertEqual(tracker.get_max(), 80, msg='max ' + msg)
        self.assertEqual(tracker.get_min(), 50, msg='min ' + msg)
        self.assertEqual(tracker.get_mean(), 70.0, msg='mean ' + msg)
        self.assertEqual(tracker.get_mode(), 80, msg='mode ' + msg)

        tracker.insert(30)
        msg = 'failed on lower temp recorded'
        self.assertEqual(tracker.get_max(), 80, msg='max ' + msg)
        self.assertEqual(tracker.get_min(), 30, msg='min ' + msg)
        self.assertEqual(tracker.get_mean(), 60.0, msg='mean ' + msg)
        self.assertEqual(tracker.get_mode(), 80, msg='mode ' + msg)


unittest.main(verbosity=2)