How to get biggest array element based on his second sub array value

Question

I have an JavaScript array of arrays:

[[-786, 2], [-783, 1], [-782, 5], [-781, 1], [-779, 2], [-778, 1], [-775, 1], [-774, 1], [-773, 1], [-771, 2], [-769, 1], [-767, 1], [-766, 1], [-763, 2], [-760, 2]]

How can I get the biggest element based on value of second element in sub array?

In case above I want to get element:

[-782, 5]

Because 5 is biggest second value in all sub arrays. If there will more than one sub arrays with the bigger second value, I'd like to get first one.

Mariusz

Answer 1

Perform a descending sort based on the second element of each element of the array.

var array = [[-786, 2], [-783, 1], [-782, 5], [-781, 1], [-779, 2], [-778, 1], [-775, 1], [-774, 1], [-773, 1], [-771, 2], [-769, 1], [-767, 1], [-766, 1], [-763, 2], [-760, 2]];


array.sort(function(a, b) {
    return b[1] - a[1];
});

console.log(array[0]);

jsFiddle Demo

Please note that while this solution is terse, using sort just for finding the largest or smallest element would be much slower than a for loop that finds the largest/smallest element in a single iteration.

Answer 2

var array = [[-786, 2], [-783, 1], [-782, 5], [-781, 1], [-779, 2], [-778, 1], [-775, 1], [-774, 1], [-773, 1], [-771, 2], [-769, 1], [-767, 1], [-766, 1], [-763, 2], [-760, 2]];
var maxElementIndex = 0;
for (var i = 0; i < array.length; i++) {
    if (array[i][1] > array[maxElementIndex][1]) {
        maxElementIndex = i;
    }
}

console.log(array[maxElementIndex]);