Java for LeetCode 112 Path Sum

標籤：

Given a binary tree and a sum, determine if the tree has a root-to-leaf path such that adding up all the values along the path equals the given sum.

For example:
Given the below binary tree and sum = 22,

              5             /             4   8           /   /           11  13  4         /  \              7    2      1

return true, as there exist a root-to-leaf path 5->4->11->2 which sum is 22.

解題思路：

遞迴，JAVA實現如下：

    public boolean hasPathSum(TreeNode root, int sum) {        if(root==null)        return false;    if(root.val==sum&&root.left==null&&root.right==null)        return true;        else return hasPathSum(root.left,sum-root.val)||hasPathSum(root.right,sum-root.val);    }

 

Java for LeetCode 112 Path Sum