T37:是否是平衡二叉树

平衡二叉树：左右树的高度差不超过1

public class TreeDepth {
	public class TreeNode {
	    int val = 0;
	    TreeNode left = null;
	    TreeNode right = null;

	    public TreeNode(int val) {
	        this.val = val;
	    }
	}
	
	  public int TreeDepth(TreeNode root) {
		
		  if(root==null){
			  return 0;  
		  }
		int leftDepth= TreeDepth(root.left);
		int rightDepth=TreeDepth(root.right);
		
		return leftDepth>rightDepth?leftDepth+1:rightDepth+1;
	        
	    }
	  
	  public boolean IsBalanced_Solution(TreeNode root) {
		  if(root==null){
			  return true;
		  }
		  int left=TreeDepth(root.left);
		  int right=TreeDepth(root.right);
		  if(Math.abs(left-right)>1){
			  return false;
		  }
		return true;
	        
	    }
}