原题地址:http://projecteuler.net/problem=5
2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.
What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20?
大意是:
2520是最小的能被1-10中每个数字整除的正整数。
最小的能被1-20中每个数整除的正整数是多少?
解法1:
1.列出20以内的质数,并求这些质数的小于20的最高次幂
2.再将这些质数的最高次幂的积相乘
python代码如下:
primelist = {2:0,3:0,5:0,7:0,11:0,13:0,17:0,19:0} def setPrimelist(): for x in primelist.keys(): num = x while num*x < 20: primelist[x] += 1 num *= x else: primelist[x] += 1 def minProduct(): sum = 1 for x in primelist.keys(): sum *= x**primelist[x] return sum if __name__ == '__main__': setPrimelist() print minProduct()
注:题目的中文翻译源自http://pe.spiritzhang.com