Question

I’m sitting over the following array-problem:

• I have four arrays 1,2,3,4
• each can contain any number of elements
• I’m looking for the array(s) with the highest number of elements (and its 2nd to last element)

I’m using this:

var arr = [],
$panels = $(':jqmData(hash="history")'),
$panels.each(function(index) {
     //data("stack") contains the array
     arr.push($(this).data("stack"));
     });
arr.sort(function(a,b){return b.length - a.length});
console.log( arr[0] );

So if the arrays look like this:
[a,b,c] [d,e] [f,g,h,i] [k,l] console says [ [f,g,h,i] ]

OK, but if two arrays have the same highest length, like so:
[a,b,c,d] [d,e] [f,g,h,i] [k,l] I don’t get [ [a,b,c,d] [f,g,h,i] ]

because arr[0] will only return the first array again.

I’m clueless…

Is there a way to give me the array or arrays with the highest number of elements and their 2nd-to-last respective element?

Thanks!

Answer 1

Use this code:

var longest = [];
var longestLen = 0;
$('div:jqmData(hash="history")').each(function(){
    var data = $(this).data("stack");
    if(data.length > longestLen){
        longest = [data];
        longestLen = data.length;
    }
    else if(data.length == longestLen) longest.push(data)
})

What happens?

1. var data = ... The array is retrieved.
2. if(data.length > longestLen) – Comparing the length of the current array to the known longest length.
   If the new array has a greater size, replace longest by a new array consisting of element data.
   Update longestLen to the length of the current longest array.
3. else if(data.length == longestLen) longest.push(data) – If the current array has the same length as the longest array, push the current array in the existing array longest.