Binary-Tree-Level-Order-Traversal-II.cs

publicclassSolution{
publicIList<IList<int>>LevelOrderBottom(TreeNoderoot){
varresult=newList<IList<int>>();
varlevel=0;
Recursion(root,result,level);
result.Reverse();
returnresult;
}

privatevoidRecursion(TreeNodenode,List<IList<int>>list,intlevel){
if(node==null)return;
if(list.Count()==level)
{
list.Add(newList<int>());
}
list[level].Add(node.val);

if(node.left!=null){
Recursion(node.left,list,level+1);
}
if(node.right!=null){
Recursion(node.right,list,level+1);
}
}
}
/**
 * Definition for a binary tree node.
 * public class TreeNode {
 * public int val;
 * public TreeNode left;
 * public TreeNode right;
 * public TreeNode(int val=0, TreeNode left=null, TreeNode right=null) {
 * this.val = val;
 * this.left = left;
 * this.right = right;
 * }
 * }
 */