摘要：
Initially on a notepad only one character 'A' is present. You can perform two operations on this notepad for each step: Given a number n. You have to 阅读全文
摘要：
Imagine you have a special keyboard with the following keys: Key 1: (A): Print one 'A' on screen. Key 2: (Ctrl-A): Select the whole screen. Key 3: (Ct 阅读全文