POJ1338 2545 2591 2247都是一个类型的题目,所以放到一起来总结 POJ1338:Ugly Numbers Time Limit: 1000MS Memory Limit: 10000K Total Submissions: 21708 Accepted: 9708 Description Ugly numbers are numbers whose only prime factors are 2, 3 or 5. The sequence 1, 2, 3, 4,…
1: 找小于最大的最大的 select max(Salary) from Employee where Salary<(select MAX(Salary) from Employee); 2. 排序 select Salary from Employee where Salary not in (select MAX(Salary)from Employee) order by Salary desc limit 1; select ( select distinct Salary from…