摘要：
Alice and Bob need to send secret messages to each other and are discussing ways to encode their messages: Alice: “Let’s just use a very simple code: 阅读全文
摘要：
Farmer John has built a new long barn, with N (2 <= N <= 100,000) stalls. The stalls are located along a straight line at positions x1,...,xN (0 <= xi 阅读全文
摘要：
Ivan, Filbert, and Tracy really like nuts. They can eat nuts without stopping all day long if they want to. Today they decided to buy some nuts so eac 阅读全文