标签:blog ane roo leaves pull solution clear treenode null
Find the sum of all left leaves in a given binary tree.
Example:
3 / 9 20 / 15 7 There are two left leaves in the binary tree, with values 9 and 15 respectively. Return 24.
1 class Solution { 2 3 public int sumOfLeftLeaves(TreeNode root) { 4 if(root==null) return 0; 5 int sum = 0; 6 if(root.left!=null){ 7 if(root.left.left==null && root.left.right==null) sum +=root.left.val; 8 else sum+=sumOfLeftLeaves(root.left); 9 } 10 sum+=sumOfLeftLeaves(root.right); 11 return sum; 12 13 } 14 15 }
标签:blog ane roo leaves pull solution clear treenode null
原文地址:http://www.cnblogs.com/zle1992/p/7768759.html