Python implements efficient prime number code examples, python Prime Number

Python implements efficient prime number code examples, python Prime Number

Prime numbers are frequently used in programming.

As an example of learning Python, the following is a program that efficiently solves prime numbers within a range. Division or modulo operations are not required.

# Coding: UTF-8 # Set the python file encoding to UTF-8, so that you can write the Chinese comment def primeRange (n): myArray = [1 for x in range (n + 1)] # list parsing: generate a list with a length of (n + 1, each value is 1 myArray [0] = 0 myArray [1] = 0 startPos = 2 while startPos <= n: if myArray [startPos] = 1: key = 2 resultPos = startPos * key # it can be seen that the integer multiples of startPos are not prime numbers. The position of the integer multiples of startPos is set to 0 to indicate non-prime numbers while resultPos <= n: myArray [resultPos] = 0 key + = 1 resultPos = startPos * key startPos + = 1 resultList = [] # Save the final prime number in the resultList list and return startPos = 0 while startPos <= n: if myArray [startPos] = 1: resultList. append (startPos) startPos + = 1 return resultListnumString = raw_input ("Input the Range (> 3):") numInt = int (numString) if numInt <= 3: print "The Number Need to be greater than 3" else: primeResult = primeRange (numInt) print "The Result is:", primeResult