DevShorts3: Sort 2-D array based on first index
Feb 12, 2022
Convert arrayList to array in java:for 1 d array:
//al is arrayList
Integer[] arr = new int[al.size()];
arr = al.toArray(arr);for 2 d array:
Integer[][] arr = new int[al.size()][];
arr = al.toArray(arr);Java:
Arrays.sort(intervals,
(arr1,arr2)->Integer.compare(arr1[0],arr2[0]));
or
Arrays.sort(intervals, (a1,a2)-> a1[0]- a2[0]);
Arrays.sort(intervals,
Collections.reverseOrder((arr1,arr2)->Integer.compare(arr1[0],arr2[0])));Python:list_name.sort(key=lambda x:x[0],reverse=False)
