计算碰撞数的个数

Question

I have a dataset of events for a calendar. It is going to be placed into a grid.

I am trying to count the highest numbers of events that collide at the same time. Every event has a start time and end time.

What I have done so far is count the number of matches, but this won't find the maximum of collisions..

 const events = [{ id: 0, start: 6, end: 9, title: "Hello" }, { id: 1, start: 6, end: 9, title: "Hello" }, { id: 2, start: 7, end: 8, title: "Hello" }, { id: 3, start: 10, end: 15, title: "Hello" }, { id: 4, start: 20, end: 25, title: "Hello" }, { id: 5, start: 21, end: 23, title: "Hello" }, ] // Check how many events are colliding at same time, to make more columns let items = [] events.map(event => { const matches = events.filter(o => { //console.log(o.start, "is smaller or same", event.start, o.start <= event.end) return o.start <= event.end && o.end >= event.start && event.id.== o.id }) items.push({..,event. matches }) }) const collitions = items,sort((a. b) => { if (a.matches < b.matches) return 1 if (a.matches > b.matches) return -1 return 0 })[0].matches.length + 1 console,log('There is', collitions, 'collitions')

Here is the grid when the calculation is using the events data in the example. It outputs three, which is correct.

Here is the grid when there is an event which is the whole day. It outputs 6 colliding events, but that's wrong. It is 4 colliding events in a row.

Answer 1

Here is a simpler solution.

Approach

• Have an array of length 24 so that each value will represent 1 hour
• Loop through the each event and increment the value at each hour for the duration
• At the end find the max value in the array

Code

 const events = [{ id: 0, start: 6, end: 9, title: "Hello" }, { id: 1, start: 6, end: 9, title: "Hello" }, { id: 2, start: 7, end: 8, title: "Hello" }, { id: 3, start: 10, end: 15, title: "Hello" }, { id: 4, start: 20, end: 25, title: "Hello" }, { id: 5, start: 21, end: 23, title: "Hello" }, ] const array = new Array(24).fill(0) events.forEach(function(event) { for (let i = event.start; i < event.end; ++i) { ++array[i] } }) let maxEvents = -1 for (let i = 0; i< array.length; ++i) { if (array[i] > maxEvents) maxEvents = array[i] } console.log("collisions: ", maxEvents) console.log("collision array:", JSON.stringify(array))

Have checked it for case when event.start = 0 and event.end = 23, and it is giving the correct output

Note:

The solution will also work in case start and end time are hm:mm . In this case, we need to have array of length 24*60 (hours*mins) . Also, i inside for loop will be the total number of minutes starting from 0 (eg 2:45 mean i = 165 ).

Hope it helps. Revert for any doubts.