本帖最后由 liumilan2009 于 2013-09-13 11:24 编辑 1 2 f_less = open('less20.txt','w') 3 f_more = open('more20.txt','w') 4 5 for line in open("test"): 6 # line = line.strip() 7 if line.find("start to print")>0 : 8 num = 0 9 word = "" 10 f_less.write(line) 11 f_more.write(line) 12 elif line.find("end to print")>0: 13 if( num <20): 14 ...
转:shirley.ren python中else语句整理 if-else语句: 和各种语言相同的用法,在条件语句中,与if语句搭配使用的else语句。如果if语句的条件表达式的结果布尔值为假,那么程序将执行else语句后的代码。它的语法是大家最为熟知的: python代码[code]if expression: expr_true_suite else: expr_false_suite [/code]elif(else-if)语句: elif是python提供的else-if语句,它检查多个条件表达式的值是否为真,并在为真...
while语句在一个条件为真的情况下,while语句允许你重复执行一块语句。直接看例子:[code]#!/usr/bin/python # Filename: while.py number = 23 running = True while running: guess = int(raw_input('Enter an integer : ')) if guess == number: print 'Congratulations, you guessed it.' running = False # this causes the while loop to stop elif guess < number: print 'No, it ...
本帖最后由 2007robot 于 2013-10-19 10:23 编辑 ---------------------------------------------- del ++++++++++++++++++++++++++++++++++++++++++++++