Elixir: Maps

🚧 In development

Instructions

🚧 In development

The exercise doesn't pass checking. What to do? 😶

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In my environment the code works, but not here 🤨

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My code is different from the teacher's one 🤔

It's fine. 🙆 One task in programming can be solved in many different ways. If your code passed all tests, it complies with the task conditions.

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I've read the lessons but nothing is clear 🙄

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Your exercise will be checked with these tests:

1defmodule Test do
2  use ExUnit.Case
3  import Solution
4
5  test "keys_sum" do
6    map = %{a: 1, b: 2, c: 42}
7    assert keys_sum(map, :a, :b) == 3
8    assert keys_sum(map, :a, :c) == 43
9    assert keys_sum(map, :c, :b) == 44
10    assert keys_sum(map, :a, :a) == 2
11    assert keys_sum(map, :a, :d) == 1
12    assert keys_sum(map, :d, :c) == 42
13    assert keys_sum(map, :d, :e) == 0
14  end
15
16  test "keys_product" do
17    map = %{one: 1, five: 5, ten: 10}
18    assert keys_product(map, :one, :five) == 5
19    assert keys_product(map, :one, :ten) == 10
20    assert keys_product(map, :five, :ten) == 50
21    assert keys_product(map, :five, :five) == 25
22    assert keys_product(map, :five, :two) == 5
23    assert keys_product(map, :two, :ten) == 10
24    assert keys_product(map, :two, :three) == 1
25  end
26
27  test "copy_key" do
28    map1 = %{a: 1, b: 2}
29    map2 = %{c: 3, d: 4}
30    assert copy_key(map1, map2, :a, 42) == %{c: 3, d: 4, a: 1}
31    assert copy_key(map1, map2, :b, 42) == %{c: 3, d: 4, b: 2}
32    assert copy_key(map1, map2, :e, 42) == %{c: 3, d: 4, e: 42}
33    assert copy_key(map1, map2, :c, 42) == %{c: 42, d: 4}
34
35    assert copy_key(map2, map1, :c, 42) == %{a: 1, b: 2, c: 3}
36    assert copy_key(map2, map1, :d, 42) == %{a: 1, b: 2, d: 4}
37    assert copy_key(map2, map1, :e, 42) == %{a: 1, b: 2, e: 42}
38    assert copy_key(map2, map1, :b, 42) == %{a: 1, b: 42}
39  end
40end
41

Teacher's solution will be available in:

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