# Leetcode 536. Construct Binary Tree from String

You need to construct a binary tree from a string consisting of parenthesis and integers.

The whole input represents a binary tree. It contains an integer followed by zero, one or two pairs of parenthesis. The integer represents the root’s value and a pair of parenthesis contains a child binary tree with the same structure.

You always start to construct the left child node of the parent first if it exists.

Note:
There will only be ‘(‘, ‘)’, ‘-‘ and ‘0’ ~ ‘9’ in the input string.
An empty tree is represented by “” instead of “()”.



# 像大佬一样

Nothing in this world can take the place of persistence. Talent will not; nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not; the world is full of educated derelicts. Persistence and determination alone are omnipotent. The slogan Press On! has solved and always will solve the problems of the human race

# http reverse proxy

1. pound

https://help.ubuntu.com/community/Pound

/etc/pound/pound.cfg

2. squid

# /etc/squid/squid.conf

# same public IP for ceph.minggr.net, www.example.com, example.com

http_port 80 vhost

cache_peer 192.168.1.1 parent 80 0 no-query originserver name=server_1
acl sites_server_1 dstdomain ceph.minggr.net
cache_peer_access server_1 allow sites_server_1

cache_peer 192.168.1.2 parent 80 0 no-query originserver name=server_2
acl sites_server_2 dstdomain www.example.com example.com
cache_peer_access server_2 allow sites_server_2