ericzhong

def binary_search(lst, num):
    if num not in lst:
        return None
    last = len(lst)
    first = 0
    while(last>first):
        mid = (last + first) / 2
        if lst[mid] == num:
            return mid
        elif lst[mid] > num:

ericzhong

def count(lst):
    r = {}
    for i in lst:
        if i in r:
            r[i] += 1
        else:
            r[i] = 1
    return r

ericzhong

### run.sh ###
#!/bin/bash

for((n=0; n<2; n++))
do
    ./print.sh $n &
done
wait

ericzhong

version: '3'
services:
  mysql:
    image: mysql:latest
    restart: always
    ports:
      - 3306:3306
    environment:
      MYSQL_ROOT_PASSWORD: 123
      MYSQL_DATABASE: test

ericzhong

a = int('101', base=2)

from functools import partial
b2i = partial(int, base=2)
b = b2i('101')


def btoi(x, base=2):
    return int(x, base)

ericzhong

from collections import Iterator

class Foo(Iterator):
    def __init__(self, stop):
        self.x = 0
        self.stop = stop

    def __iter__(self):
        return self

ericzhong

def gen(stop):
    for i in range(stop):
        yield i

f = gen(10)
print(type(f))

for i in f:
    print(i),

ericzhong

def gen(stop):
    i = 0
    while True:
        if i >= stop:
            raise StopIteration
        i = (yield i) or i+1

g = gen(100)
print(next(g))    # Python 3 compatibility
print(next(g))

ericzhong

def log(func):
    def foo():
        print('call %s' % func.__name__)
        return func()
    return foo

@log
def test():
    pass

ericzhong

# Method-1
class Foo(object):
    __instance = None
    def __new__(cls, *args, **kwargs):
        if Foo.__instance is None:
            Foo.__instance = object.__new__(cls, *args, **kwargs)
        return Foo.__instance

a = Foo()
b = Foo()