Daily Challenge #185 - House Numbers Sum

Setup

A boy is walking home from school. To make the walk more enjoyable, he decides to add up the numbers of the houses he passes during his walk. Unfortunately, the numbers won't appear to him in any specific order, since he's regularly taking turns.

At some point during the walk, the boy encounters a house marked number 0. This surprises him so much that he stops adding the numbers after that house to the total.

For the given array of house numbers, determine the sum that the boy will get. There will always be at least one number 0 house on the path.

Examples

inputArray = [5, 1, 2, 3, 0, 1, 5, 0, 2] => 11

inputArray = [1, 4, 34, 124, 2, 0, 14, 51] => 165

Tests

inputArray = [5, 1, 2, 3, 0, 1, 5, 0, 2]

inputArray = [4, 2, 1, 6, 0]

inputArray = [4, 1, 2, 3, 0, 10, 2]

Good luck!

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This challenge comes from myjinxin2015 on CodeWars. Thank you to CodeWars, who has licensed redistribution of this challenge under the 2-Clause BSD License!

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Comments

[Matt Ellen]

If a test case doesn't have an expected output, is it really a test case?

Also, what did the boy do for houses with numbers like "14A" or houses that have names, and no number?

[Madza]

const sum = arr.slice(0, arr.indexOf(0)).reduce((a, b) => a + b, 0);

[Valts Liepiņš]

My original solution in Ruby

def houseNumSum arr
    arr.reduce(0) do |result,x|
        return result if x == 0
        result += x
    end
end

and after being inspired by Craig's solution:

def houseNumSum arr
    arr.take_while {|x| x != 0}.sum
end

[testingpro]

JavaScript

const sum = inputArray =>
inputArray.slice(0, inputArray.indexOf(0)).reduce((a, b) => a+b);
sum(inputArray);

[Nicolas Hervé]

Javascript

const sum = (arr) => arr.slice(0, arr.indexOf(0)).reduce((acc, curr) => acc + curr, 0);

[Vidit Sarkar]

C++ solution

int sumHouse(vector<int> numbers){
    int sum = 0;
    for(int i: numbers){
        if(i==0)
            return sum;
        sum += i;
    }
}

[Craig McIlwrath]

Simple Haskell solution

houseSum :: (Eq a, Num a) => [a] -> a
houseSum = sum . takeWhile (/=0)

[SavagePixie]

Elixir

defmodule Challenge do
  def housenumsum([ 0 | _tail ]), do: 0
  def housenumsum([ head | tail ]), do: head + housenumsum(tail)
end