Code Fights - avoidObstacles

README.md

You are given an array of integers representing coordinates of obstacles situated on a straight line.

Assume that you are jumping from the point with coordinate 0 to the right. You are allowed only to make jumps of the same length represented by some integer.

Find the minimal length of the jump enough to avoid all the obstacles.

Example

For inputArray = [5, 3, 6, 7, 9], the output should be
avoidObstacles(inputArray) = 4.

Input/Output

• [time limit] 4000ms (py3)

• [input] array.integer inputArray

  Non-empty array of positive integers.

  Guaranteed constraints:

  2 ≤ inputArray.length ≤ 10,
  1 ≤ inputArray[i] ≤ 40.
  

• [output] integer

  The desired length.

avoid_obstacles.py

from typing import List


class AvoidObstacles:
    @classmethod
    def avoid_obstacles(cls, obstacles: List[int]) -> int:
        min_len = 2
        found = False
        while not found:
            if cls._valid_length(obstacles, min_len):
                return min_len
            elif min_len > 40:
                return -1
            else:
                min_len += 1

    @classmethod
    def _valid_length(cls, obstacles: List[int], length: int) -> bool:
        for o in obstacles:
            if o % length == 0:
                return False
        return True

avoidObstacles.py

def avoidObstacles(obstacles: list) -> int:
    min_len = 2
    found = False
    while not found:
        if _valid_length(obstacles, min_len):
            return min_len
        elif min_len > 40:
            return -1
        else:
            min_len += 1


def _valid_length(obstacles: list, length: int) -> bool:
    for o in obstacles:
        if o % length == 0:
            return False
    return True

test_avoid_obstacles.py

import unittest
from avoid_obstacles import AvoidObstacles


class TestAvoidObstacles(unittest.TestCase):
    def test_1(self):
        data = [5, 3, 6, 7, 9]
        solution = 4
        result = AvoidObstacles.avoid_obstacles(data)
        self.assertEqual(result, solution)

    def test_2(self):
        data = [2, 3]
        solution = 4
        result = AvoidObstacles.avoid_obstacles(data)
        self.assertEqual(result, solution)

    def test_3(self):
        data = [1, 4, 10, 6, 2]
        solution = 7
        result = AvoidObstacles.avoid_obstacles(data)
        self.assertEqual(result, solution)


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