题解 | #二叉树中和为某一值的路径(一)#

import java.util.*;

/*
 * public class TreeNode {
 *   int val = 0;
 *   TreeNode left = null;
 *   TreeNode right = null;
 * }
 */

public class Solution {
    /**
     * 
     * @param root TreeNode类 
     * @param sum int整型 
     * @return bool布尔型
     */
    public boolean hasPathSum (TreeNode root, int sum) {
        if(root == null) return false;
        sum -= root.val;
        if(sum == 0 && root.left == null && root.right == null) return true;
        return hasPathSum(root.left,sum ) || hasPathSum(root.right,sum);        
    }
}