g1201_1300.s1203_sort_items_by_groups_respecting_dependencies

Class Solution

java.lang.Object

g1201_1300.s1203_sort_items_by_groups_respecting_dependencies.Solution

public class Solution
extends Object

1203 - Sort Items by Groups Respecting Dependencies.

Hard

There are n items each belonging to zero or one of m groups where group[i] is the group that the i-th item belongs to and it’s equal to -1 if the i-th item belongs to no group. The items and the groups are zero indexed. A group can have no item belonging to it.

Return a sorted list of the items such that:

• The items that belong to the same group are next to each other in the sorted list.
• There are some relations between these items where beforeItems[i] is a list containing all the items that should come before the i-th item in the sorted array (to the left of the i-th item).

Return any solution if there is more than one solution and return an empty list if there is no solution.

Example 1:

Input: n = 8, m = 2, group = [-1,-1,1,0,0,1,0,-1], beforeItems = [[],[6],[5],[6],[3,6],[],[],[]]

Output: [6,3,4,1,5,2,0,7]

Example 2:

Input: n = 8, m = 2, group = [-1,-1,1,0,0,1,0,-1], beforeItems = [[],[6],[5],[6],[3],[],[4],[]]

Output: []

Explanation: This is the same as example 1 except that 4 needs to be before 6 in the sorted list.

Constraints:

• 1 <= m <= n <= 3 * 104
• group.length == beforeItems.length == n
• -1 <= group[i] <= m - 1
• 0 <= beforeItems[i].length <= n - 1
• 0 <= beforeItems[i][j] <= n - 1
• i != beforeItems[i][j]
• beforeItems[i]does not contain duplicates elements.

Constructor Summary

Constructors

Constructor and Description
Solution()

Method Summary

Modifier and Type	Method and Description
int[]	sortItems(int n, int m, int[] group, List<List<Integer>> beforeItems)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Solution

public Solution()

Method Detail

sortItems

public int[] sortItems(int n,
                       int m,
                       int[] group,
                       List<List<Integer>> beforeItems)