Connecting The Dots: Front-end and Algorithms

Input: intervals = [[1,3],[2,6],[8,10],[15,18]]Output: [[1,6],[8,10],[15,18]]Explanation: Since intervals [1,3] and [2,6] overlaps, merge them into [1,6].

Input: intervals = [[1,4],[4,5]]Output: [[1,5]]Explanation: Intervals [1,4] and [4,5] are considered overlapping.

const merge = (currentList, newList) => {    // We take the currentList at first load, and the "load more" list.    // First we just merge it by spread operator => [...currentList, ...newList]    // After that we use `Array.prototype.reduce` to generate a new array,    // Which is merged and grouped by date.  const merged = [...currentList, ...newList].reduce((acc, item) => {        // Condition 1: just push the item to the new empty array, or        // if the last item in `acc` doesn't have the same date with the current item    if (!acc.length || acc[acc.length - 1].date !== item.date) {      acc.push(item);    } else {            // Condition 2: if they have the same date, we merge it.       const lastItem = acc[acc.length - 1];      const mergedDate = [...lastItem.transactions, ...item.transactions];      lastItem.transactions = mergedDate;    }    return acc;  }, []);  return merged;};const result = await fakeAPIRequest(page);setMergedList((prevList) =>    merge(cloneDeep(prevList), cloneDeep(result.items)));