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@xiaotdl
xiaotdl / intro_to_web_dev.md
Last active June 17, 2018 06:53
Introduction to website developing
@xiaotdl
xiaotdl / rabbitmq.txt
Created May 21, 2018 22:32 — forked from sdieunidou/rabbitmq.txt
create admin user on rabbitmq
rabbitmqctl add_user test test
rabbitmqctl set_user_tags test administrator
rabbitmqctl set_permissions -p / test ".*" ".*" ".*"
@xiaotdl
xiaotdl / subprocess
Last active September 30, 2016 18:12
import logging
import tempfile
import subprocess
class Result(object):
def __init__(self, rc, stdout, stderr, cmd):
self.rc = rc
self.stdout = stdout
self.stderr = stderr
"""
1.5 Implement a method to perform basic string compression using the counts
of repeated characters. For example, the string aabcccccaaa would become
a2b1c5a3. If the "compressed" string would not become smaller than the original
string, your method should return the original string.
"""
# Complexity: time O(n), space O(n)
def compress_string(string):
if not string:
return
"""
1.4 Write a method to replace all spaces in a string with '%20'. You may assume that
the string has sufficient space at the end of the string to hold the additional
characters, and that you are given the "true" length of the string. (Note: if implementing
in Java, please use a character array so that you can perform this operation
in place.)
EXAMPLE
Input: "Mr John Smith "
Output: "Mr%20Dohn%20Smith"
"""
1.3 Given two strings, write a method to decide if one is a permutation of the other.
tips:
assumption - case sensitive, whitespace matters
"""
# sort string and compare
# Complexity: time O(nlogn), space O(1)
def is_permutation(str1, str2):
if not str1 or not str2 or len(str1) != len(str2):
return False
"""
1.2 Implement a function void reverse(char* str) in C or C++ which reverses a null terminated string.
"""
# In python, str is immutable
# Complexity: time O(n), space O(n)
def reverse_string(string):
if not string:
return
res = ""
for i in range(1, len(string) + 1):
"""
1.1 Implement an algorithm to determine if a string has all unique characters. What if you cannot use additional data structures.
tips:
encodings - anscii, latin1, unicode
corner case - empty string's return value
"""
# assume ascii case
# Complexity: time O(n), space O(1)
def unique_chars(string):
if not string or len(string) > 128: