python语法 之 循环迭代

# -*- coding:utf-8 -*-#while 条件:#    代码块11#else:#    代码块2i=1while i<=5:    print '第'+str(i)+'次输出'    i+=1 #语法没有i++else:    print '完毕'#for one in object:#    代码块1#    if 条件1:#        break#    if 条件2:#        continue#    else:#        passnums=[1,2,3,4,5]for num in nums:    print num###所谓字典:由“键-值”组成的集合#dic = {'1':'a','2':'b'}for key in dic:    print key,'----',dic[key]#for循环遍历元祖：tuple=[(1,2),(3,4)]for a,b in tuple:    print a,b#||for (a,b) in tuple:    print a,bfor a in tuple:    print a#迭代器#任何类似的对象都被认为是可迭代的。迭代工具的内部工作都是在循环调用next方法，#并且捕捉StopIteration异常来确定何时离开。for readline in open('test.py'):    print readline#iter()内置函数many = [1,2,3,4,5]one = iter(many)print one.next();print one.next();print one.next();print one.next();###直接for循环#for one in iter(many):    print one#九九乘法表for i in range(1,10):    for j in range(1,i+1):        print (" ".join(["%d*%d=%d" %(j,i,i*j)]))#并行迭代names=['a','b']ages=[1,2]for i in range(len(names)):    print names[i],'----',ages[i]#zip迭代是把两个序列“压缩”在一起，然后返回一个元祖的列表for name,age in zip(names,ages):    print name,'-------',age#编号迭代for index,name in enumerate(names):    if 'a' in names:        names[index]='aaa'        print index,name        for name in names:            print name