I need to break an array of objects into a 2-dimensional array where 1-dimensional arrays would consist of objects which have their attributes ‘for’ and ‘to’ being not overlapping intervals.

Example: Given array arr1 I wish to receive arr2

const arr1 = [ { from: 0, to: 2, }, { from: 0, to: 6, }, { from: 3, to: 7, }, { from: 2, to: 4, }, ] arr2 = [ [ { from: 0, to: 2, }, { from: 3, to: 7, } ], [ { from: 0, to: 6, } ], [ { from: 2, to: 4, } ], ]

How it should work: We loop through the arr1. Object1 should be put into the first 1-dimensional array in arr2 by default.

Object2 overlaps with Object1 so it should be put into a separate array in arr2.

Object3 does not overlap Object1 so it should be put into the first 1-dimensional array with Object1

Object4 overlaps with Object1 so it should be put into the second 1-dimensional array to Object3, but it also overlaps with Object3 so it should be put into a separate 1-dimensional array.

I need to find the solution with as less loops as possible)

## Answer

You could iterate the result array and find a slot if all items do not overlap.

const array = [{ from: 0, to: 2 }, { from: 0, to: 6 }, { from: 3, to: 7 }, { from: 2, to: 4 }], result = array.reduce((r, o) => { if (!r) return [[o]]; const group = r.find(a => a.every(({ from, to }) => o.to <= from || to <= o.from)); if (group) group.push(o); else r.push([o]); return r; }, undefined); console.log(result);

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