Leaf_Similar_Trees.java

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     int val;
 *     TreeNode left;
 *     TreeNode right;
 *     TreeNode() {}
 *     TreeNode(int val) { this.val = val; }
 *     TreeNode(int val, TreeNode left, TreeNode right) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
class Solution {
    public boolean leafSimilar(TreeNode root1, TreeNode root2) {
        ArrayList<Integer> list1=new ArrayList<Integer>();
        ArrayList<Integer> list2=new ArrayList<Integer>();
        dfs(root1,list1);
        dfs(root2,list2);
       return (list1.equals(list2)); 
    }
    public void dfs(TreeNode root, List<Integer> list)
    {
        if(root==null)
            return;
        else
        {
            if(root.left==null && root.right==null)
                list.add(root.val);
            dfs(root.left,list);
            dfs(root.right,list);
        }
    }
}