I'm trying to solve this kata:

You are given a list of unique integers arr, and two integers a and b. Your task is to find out whether or not a and b appear consecutively in arr, and return a boolean value (True if a and b are consecutive, False otherwise).

It is guaranteed that a and b are both present in arr.

Test examples:

consecutive([1, 3, 5, 7], 3, 7), false
consecutive([1, 3, 5, 7], 3, 1), true 
consecutive([1, 6, 9, -3, 4, -78, 0], -3, 4), true

This is what I have so far:

for (let i = 0; i < arr.length; i  ) {
  let index2 = arr.indexOf(b)
  let index1 = arr.indexOf(a)

    let diff = (index2) - (index1)

    if (diff > 1) {
        console.log(diff, 'false');
        return false
    } else {
        console.log(diff, 'true');
        return true
    }
}

The test examples are passing but then when I submit the solution, some other tests are not passing. I don't get to see the tests that are not passing so I'm stuck on this. Also, I thought that, in case a and b are the same number, so in case I had

cons([4, 6, 4, 5, 6], 4, 4)

my solution wouldn't pass this test, so how could I improve it?

CodePudding user response：

To answer your question, the reason your code isn't passing all the tests is because you are not taking into account that when a comes after b, diff will be negative.

So you should be doing

let diff = Math.abs(index2 - index1)

Also the for loop doesn't seem to do anything so you can just delete it.

CodePudding user response：

steps:

1. Find index of given values
2. check if index of any one value or - 1 is same as other.

code:

function consecutive(number_list, value1,value2){
    var index_value_one = number_list.indexOf(value1);
  var index_value_two = number_list.indexOf(value2);
  
  if(index_value_one == (index_value_two   1) || index_value_one == (index_value_two - 1)){
  return true;
  }
  return false;
  
}

console.log(consecutive([1, 3, 5, 7], 3, 7));
console.log(consecutive([1, 3, 5, 7], 3, 1));
console.log(consecutive([1, 6, 9, -3, 4, -78, 0], -3, 4));

output: