凯撒加密与解密及其python代码的实现

1.凯撒加密

2.代码的实现

def change(c,i):
c = c.lower()
num = ord(c)
if num >= 97 and num <= 122:
num = 97 + ((num - 97) + i) % 26
return chr(num)

def kaisa_jiami(string,i):
string_new = ''
for s in string:
string_new += change(s,i)
print(string_new)
return string_new

def kaisa_jiemi(string):
for i in range(25):
print('\n', i, '\n')
i += 1
kaisa_jiami(string,i)

def main():
print('请选择需要的操作：')
print('1：凯撒加密')
print('2：凯撒解密')
choice = input()
if choice == '1':
string = input('请输入需要加密的字符串：')
num = int(input('请输入需要偏移的位数：'))
kaisa_jiami(string,num)
elif choice == '2':
string = input('请输入需要解密的字符串：')
kaisa_jiemi(string)
else:
print('输入错误，请重试！')
main()

if __name__ == '__main__':
main()

3.效果