2. q1全部offer/append到q2. 3. 用一个Temp做swap q1, q2. q1的头，就一直是最后加进去的值. 2 queue are like two cups. We are fliping water into/out ...

In this lab module, you'll explore the power of stacks and queues in Java by solving real-world-inspired problems. You'll balance parentheses for valid expressions, reverse strings efficiently, ...