Problem Statement  
In biology, organisms have the following property: Starting from the first cell (the zygote), each cell during an organism's development process either divides into 2 other cells or does not divide at all. An organism is mature when all of its cells will not divide any further. Let's assign a unique number to each cell in an organism's development process. For example, consider a species in which each organism starts with cell 0, which divides into cells 1 and 2. Cell 1 divides into cells 3 and 4. Cells 2, 3 and 4 do not divide. Every mature organism of this species will consist of exactly 3 cells  2, 3 and 4. During the development process, if we kill a cell, it will be absent in the mature form of the organism. If that cell happens to be a cell that divides, then the mature organism will be missing all of the cell's descendants as well because the cell is killed before it has a chance to divide. For example, in the organism described above, if we kill cell 1 during the development process, the mature organism will contain only cell 2. You are given a int[] parentCell describing the development process of an organism. The ith element of parentCell is the parent cell of cell i (where i is a 0based index). The zygote's parent is 1. Return the number of cells the mature form of this organism would have if you killed cell deletedCell during the development process.  
Definition  
 
Constraints  
  parentCell will contain exactly N elements, where N is an odd integer between 1 and 50, inclusive.  
  There will be exactly one "1" element in parentCell.  
  Every element of parentCell will be between 1 and N1, inclusive.  
  parentCell will form a binary tree.  
  deletedCell will be between 0 and N1, inclusive.  
Examples  
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