Javascript - Check numeric range overlapping in array

Question

I have an array of time ranges with start & end values.

var timeRanges = [{
    start: 120,
    end: 140
},{
    start: 180,
    end: 220
},{
    start: 250,
    end: 300
}]

Need to check whether the selected range overlap the time range or not. And also the selected range should be in between the timeRange intervals. (Ex: 140-180, 220-250)

var selected = {
    start: 150,
    end: 170
}

Answer 1

Time interval B 'overlaps' A if:

• B starts after A starts but before A finishes.
• B starts before A starts and finishes after A starts.

So you can write a function which decides exactly that.

function areOverlapping(A, B) {
    if(B.start < A.start) {
        return B.finish > A.start;
    }
    else {
        return B.start < A.finish;
    }
}

Answer 2

 const overlaps = timeRanges.some( range => 
  (range.start < selected.start && range.end > selected.start) || 
  (range.start < selected.end && range.end > selected.end) || 
  (range.start > selected.start && range.end < selected.end)
 );