PS: 给一个池子里放水,at a constant rate of 50 liters per minute, 问how many hours it will take to 注满2/3 的一个水池,此水池的capacity已知(数字忘了), 并给了转换单位的公式 1 liter=1000 毫升。
DS 题: k=k+1 when k is odd k-1 when k is even,问 isa^2*b even or not? 1)a is even 2)b is odd (补充说明:具体2个条件中a,b哪个是奇,哪个是偶LZ记不清了,可能写反了,但是题大概就是这个意思,大家了解思路就行了)