二叉树的所有路径

输入:

   1
 /   \
2     3
 \
  5

输出: ["1->2->5", "1->3"]

解释: 所有根节点到叶子节点的路径为: 1->2->5, 1->3

const binaryTreePaths = function(root) {
    if (!root) return []

    const res_path = []
    const queue = [root]
    const path = [root.val.toString()]

    while(queue.length) {
        const current_node = queue.shift()
        const current_path = path.shift()

        if (!current_node.left && !current_node.right) {
            res_path.push(current_path)
        }else{
            if (current_node.left) {
                queue.push(current_node.left)
                path.push(current_path+"->"+current_node.left.val.toString())
            }
            if (current_node.right) {
                queue.push(current_node.right)
                path.push(current_path+"->"+current_node.right.val.toString())
            }
        }
    }

    return res_path
};