45. Python 小练习

需求1：

ABCD * 9 = DCBA

通过计算方法，给我们计算出 A = ?  B = ?  C = ?  D = ?

A: 1-9

B: 0-9

C: 0-9

D: 1-9

A != B != C != D

代码：

class CountNumber(object):
    def __init__(self):
        print("ABCD * 9 = DCBA; A != B != C != D")
    def numAbcd(self):
        for A in range(1, 10):
            for B in range(0, 10):
                for C in range(0, 10):
                    for D in range(1, 10):
                        if ( A * 1000 + B * 100 + C * 10 + D) * 9 == (D * 1000 + C * 100 + B * 10 + A):
                            print("{0}{1}{2}{3} * 9 = {4}{5}{6}{7}".format(A, B, C, D, D, C, B, A))
                            print("A = {0}, B = {1}, C = {2}, D = {3}".format(A, B, C, D))



def main():
    countNumber = CountNumber()
    countNumber.numAbcd()

if __name__ == '__main__':
    main()

需求2：

_____________

|_A_|_B_|_C_|

|_D_|_E_|_F_|

|_G_|_H_|_I_|

A, B, C, D, E, F, G, H, I 必须是1-9数字，且不能重复

所有的行，列，对角线的和都为15

class NinePaper(object):
    def __init__(self):
        self.numbers = list()
        for i in range(1, 10):
            self.numbers.append(i)
        print("numbers = {0}".format(self.numbers))
    def run(self):
        for A in range(1, 10):
            l1 = list()
            l1 += self.numbers
            l1.remove(A)
            for B in l1:
                l2 = list()
                l2 += l1
                l2.remove(B)
                for C in l2:
                    l3 = list()
                    l3 += l2
                    l3.remove(C)
                    for D in l3:
                        l4 = list()
                        l4 += l3
                        l4.remove(D)
                        for E in l4:
                            l5 = list()
                            l5 += l4
                            l5.remove(E)
                            for F in l5:
                                l6 = list()
                                l6 += l5
                                l6.remove(F)
                                for G in l6:
                                    l7 = list()
                                    l7 += l6
                                    l7.remove(G)
                                    for H in l7:
                                        l8 = list()
                                        l8 += l7
                                        l8.remove(H)
                                        for I in l8:
                                            if A+B+C == D+E+F == G+H+I == A+D+G == B+E+H == C+F+I == A+E+I == C+E+G == 15:
                                                print('''
                                            _____________
                                            |_{0}_|_{1}_|_{2}_|
                                            |_{3}_|_{4}_|_{5}_|
                                            |_{6}_|_{7}_|_{8}_|
                                                '''.format(A, B, C, D, E, F, G, H, I))




def main():
    ninePaper = NinePaper()
    ninePaper.run()

if __name__ == '__main__':
    main()

需求3：

将文件passwd的内容，写入新的文件并排序，新文件名为newpasswd

import codecs

import os


class SortPasswd(object):
    def __init__(self):
        self.passwd = "passwd"
        self.newpasswd = "newpasswd"
        self.contextList = list()
        if not os.path.exists(self.passwd):
            print("please download passwd from linux.")
            exit(1)
        print("sort file is :{0}".format(self.passwd))
        print("sorted file is :{0}".format(self.newpasswd))
    def getContextList(self):
        with codecs.open("passwd") as fr:
            self.contextList += sorted(fr.readlines(), key=lambda line:int(line.split(":")[2]), reverse=False)
    def writeContextList(self):
        with codecs.open("new_passwd", "w") as fw:
            fw.writelines(self.contextList)



def main():
    sortpasswd = SortPasswd()
    sortpasswd.getContextList()
    sortpasswd.writeContextList()

if __name__ == '__main__':
    main()