TwoSum - Integers and Arrays

Question

Question

Given an array of integers, return indices of the two numbers such that they add up to a specific target.

You may assume that each input would have exactly one solution, and you may not use the same element twice.

Example

Given nums = [2, 7, 11, 15], target = 9,

Because nums[0] + nums[1] = 2 + 7 = 9, return [0, 1].

Attempt

const twoSum = function(nums, target) {
    for(let i in nums){
      for(let j in nums) {
        if(nums[i] + nums[j] === target) {
            return ([nums[i], nums[j]]);
        }
      }
    }
};

console.log(twoSum([2, 7, 11, 15], 9));

Right now it's returning [2, 7]. I'm trying to return the index of both.
What am I mixing up here?

It says you need to return an *array* - you're not returning an array, you're invoking the comma operator. — CertainPerformance, Mar 21 '20 at 05:44
@CertainPerformance changed my attempt, not invoking comma operator now — and1, Mar 21 '20 at 05:46
You're returning the *values* - the `nums[i]` and `nums[j]`, but the instructions say to return the *indicies* — CertainPerformance, Mar 21 '20 at 05:47
@CertainPerformance wouldn't using a `for-in` loop return the index of elements? — and1, Mar 21 '20 at 05:51
Yes, the variable you declare in a `for..in` loop refer to the indicies. Look at your `for` loop declaration to see which variables you're declaring. — CertainPerformance, Mar 21 '20 at 05:51
Did you look at your `for` loop declarations? Eg `for(let i in nums){` do you see the name of the variable you're declaring here? — CertainPerformance, Mar 21 '20 at 05:55
@CertainPerformance yes, but im not sure what about it that im missing, changing it to another variable name doesn't change the results, so not sure — and1, Mar 21 '20 at 05:56
`for(let i in nums){` initializes an `i` variable. That's the variable you need to use. Same sort of thing for `for(let j in nums) {` — CertainPerformance, Mar 21 '20 at 05:57
@CertainPerformance so maybe `return ([indexOf(i), indexOf(j)]` or something? — and1, Mar 21 '20 at 06:02
The variables you declared are `i` and `j`. You need to return them in an array. The syntax for this is `return [i, j]` — CertainPerformance, Mar 21 '20 at 06:02
@CertainPerformance ah icic, but actually i tried with a test case, `[3, 2, 4], 6` and it's giving me `[0, 0]`, when it should be `[1, 2]` — and1, Mar 21 '20 at 06:06
You aren't allowed to return the same index. Check that they aren't the same first. — CertainPerformance, Mar 21 '20 at 06:08
@CertainPerformance something in the if statement like, `|| i != j` or something? — and1, Mar 21 '20 at 06:31
@CertainPerformance gotcha, adding the `and` part fixed it, appreciate it — and1, Mar 21 '20 at 06:45

TwoSum - Integers and Arrays

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