Package g1701_1800.s1764_form_array_by_concatenating_subarrays_of_another_array

Class Solution

java.lang.Object

g1701_1800.s1764_form_array_by_concatenating_subarrays_of_another_array.Solution

public class Solution
extends Object

1764 - Form Array by Concatenating Subarrays of Another Array.

Medium

You are given a 2D integer array groups of length n. You are also given an integer array nums.

You are asked if you can choose n disjoint subarrays from the array nums such that the ith subarray is equal to groups[i] ( 0-indexed ), and if i > 0, the (i-1)th subarray appears before the ith subarray in nums (i.e. the subarrays must be in the same order as groups).

Return true if you can do this task, and false otherwise.

Note that the subarrays are disjoint if and only if there is no index k such that nums[k] belongs to more than one subarray. A subarray is a contiguous sequence of elements within an array.

Example 1:

Input: groups = [[1,-1,-1],[3,-2,0]], nums = [1,-1,0,1,-1,-1,3,-2,0]

Output: true

Explanation: You can choose the 0^th subarray as [1,-1,0, 1,-1,-1 ,3,-2,0] and the 1^st one as [1,-1,0,1,-1,-1, 3,-2,0 ]. These subarrays are disjoint as they share no common nums[k] element.

Example 2:

Input: groups = [[10,-2],[1,2,3,4]], nums = [1,2,3,4,10,-2]

Output: false

Explanation: Note that choosing the subarrays [1,2,3,4 ,10,-2] and [1,2,3,4, 10,-2 ] is incorrect because they are not in the same order as in groups. [10,-2] must come before [1,2,3,4].

Example 3:

Input: groups = [[1,2,3],[3,4]], nums = [7,7,1,2,3,4,7,7]

Output: false

Explanation: Note that choosing the subarrays [7,7, 1,2,3 ,4,7,7] and [7,7,1,2, 3,4 ,7,7] is invalid because they are not disjoint. They share a common elements nums[4] (0-indexed).

Constraints:

• groups.length == n
• 1 <= n <= 103
• 1 <= groups[i].length, sum(groups[i].length) <= 103
• 1 <= nums.length <= 103
• -107 <= groups[i][j], nums[k] <= 107

Constructor Summary

Constructors

Constructor	Description
Solution()

Method Summary

Modifier and Type	Method	Description
boolean	canChoose(int[][] groups, int[] nums)

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

canChoose

public boolean canChoose(int[][] groups,
                         int[] nums)