Leetcode 1282. Group the People Given the Group Size They Belong To

Input: groupSizes = [3,3,3,3,3,1,3]
Output: [[5],[0,1,2],[3,4,6]]
The first group is [5]. The size is 1, and groupSizes[5] = 1.
The second group is [0,1,2]. The size is 3, and groupSizes[0] = groupSizes[1] = groupSizes[2] = 3.
The third group is [3,4,6]. The size is 3, and groupSizes[3] = groupSizes[4] = groupSizes[6] = 3.
Other possible solutions are [[2,1,6],[5],[0,4,3]] and [[5],[0,6,2],[4,3,1]].
Input: groupSizes = [2,1,3,3,3,2]
Output: [[1],[0,5],[2,3,4]]
  • groupSizes.length == n
  • 1 <= n <= 500
  • 1 <= groupSizes[i] <= n
  1. create a map, and put same group size people into the list
  2. if list size match the group size number, add it into the result list, and remove the list from map
  3. In this answer, it had at least one answer, so no need to worry if anyone didn’t join the group
  4. We could know that after the end of loop, the map should be empty



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Gary Chiang

Gary Chiang

CS new grad, 6 years experience related to supply chain management. Located in Bay area