摘要：
Problem Description A number whose only prime factors are 2,3,5 or 7 is called a humble number. The sequence 1, 2, 3, 4, 5, 6,... 阅读全文
摘要：
类似的题目有HDU1058 humble number（翻译下来都是丑陋的数字）。 Description Ugly numbers are numbers whose only prime factors are 2, 3 or 5. The sequ... 阅读全文