# Prime Path

The ministers of the cabinet were quite upset by the message from the Chief of Security stating that they would all have to change the four-digit room numbers on their offices.
— It is a matter of security to change such things every now and then, to keep the enemy in the dark.
— But look, I have chosen my number $1033$ for good reasons. I am the Prime minister, you know!
— I know, so therefore your new number $8179$ is also a prime. You will just have to paste four new digits over the four old ones on your office door.
— No, it’s not that simple. Suppose that I change the first digit to an $8$, then the number will read 8033 which is not a prime!
— I see, being the prime minister you cannot stand having a non-prime number on your door even for a few seconds.
— Correct! So I must invent a scheme for going from $1033$ to $8179$ by a path of prime numbers where only one digit is changed from one prime to the next prime.

# 第六章——字符串操作

• 字符串以单（双）引号开始，单（双）引号结束

• 在字符串开始的引号之前加上r，可以将字符串称为原始字符串，打印出字符串中所有的\之类的转义字符

# 第五章——字典和结构化数据

## 字典

• 字典的索引被称为键，键及其关联的值称为键-值。字典输入的时候要带花括号{}，在使用的时候和列表一样使用中括号[]

from numpy import*导入numpy模块

random.rand()用来生成一个随机数组

# 第三章——函数

• None表示没有值，是NoneType数据类型的唯一值。print的返回值就是None

• print()函数有可选的变元endsep，分别指定在参数末尾打印什么，在参数之间打印什么来隔开它们

# 第一章——Python基础

** 指数 $2**3$ $8$
% 取模 $22\%8$ $6$
// 整除 $22//8$ $2$
/ 除法 $22/8$ $2.75$

vim的配置文件

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