下面的练习本身不难，比如打印1到10，计算1+2+3+...+100 ,最后一个是计算 1-2+3-4...-100

用了类的方法实现

用了列表生成器

用“高级”一丢丢的写法来实现这些小练习

# coding:utf-8

class Num(object):

    def __init__(self, calNum):

        self.calNum = calNum

    @property

    def seqNum(self):

        i = 0

        while i < self.calNum:

            i += 1

            yield i

    @property

    def sumNum(self):

        return reduce(lambda sum, x: sum + x, xrange(self.calNum))

    @property

    def oddNum(self):

        return [ num for num in range(self.calNum) if num % 2 != 0 ]

    @property

    def evenNum(self):

        return [ num for num in range(self.calNum) if num % 2 == 0 ]

    @property

    def crossSumNum(self):

        sum = 0

        for i in xrange(self.calNum):

           if i % 2 == 0:

               sum = sum - i

           else:

               sum = sum + i

        return sum

def Main():

    print "======================="

    print u"输出1,2,3...10"

    print "======================="

    n = Num(10)

    for i in n.seqNum:

        print i,

    print "\r"

    print "======================="

    n = Num(101)

    print u"求和1+2+3+...+100"

    print "======================="

    print n.sumNum

    print "======================="

    print u"输出1...100范围的奇数"

    print "======================="

    for i in n.oddNum:

        print i,

    print "\r"

    print "======================="

    print u"1...100范围的偶数"

    print "======================="

    for i in n.evenNum:

        print i,

    print "\r"

    print "======================="

    print u"求和1-2+3-4-5+6...+100"

    print "======================="

    print n.crossSumNum

if __name__ == '__main__':

    Main()