Javascript: add a new value to a set of values (minutes), which is furthest away from any two existing cronjobs

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Suppose I have an array of numbers (which indicate the minutes when cron jobs should run):

let arr = ['21', '23', '25', '59', '10']

I want to insert a new number into this array arr, but I want to make sure that it's furthest away from any two numbers that already exist in this spectrum.

Intuitively I can say that it should be somewhere around 44 but how do I program that into an algorithm?

I know the question is a bit general, but it is very useful for scheduling cronjobs automatically, so that they don't overlap, and I don't even know where to start.

Maybe you heard of a similar problem and a possible solution? Or a Node.Js module that does something similar?

cron arrays javascript
1 Answers

If the values of the array are in order, you could check a value and the previous value, pic the greatest delta and calculate the time in the middle.

    let array = [35, 23, 25, 59, 10];

    array.sort((a, b) => a - b); // sorts numbers in ascending order

    let result = array
        .reduce((r, value, i, { length, [(i + length - 1) % length]: prev }) => {
            var delta = (value + 60 - prev) % 60;
            if (!r || delta > r.delta) return { delta, value: (prev + delta / 2) % 60 };
            return r;
        }, undefined)
        .value;

console.log(result);
console.log(parseInt(result)); // in case if used for cron

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