摘要：
A lot of battleships of evil are arranged in a line before the battle. Our commander decides to use our secret weapon to eliminate the battleships. Ea 阅读全文
摘要：
For the daily milking, Farmer John's N cows (1 ≤ N ≤ 50,000) always line up in the same order. One day Farmer John decides to organize a game of Ultim 阅读全文
摘要：
Painting some colored segments on a line, some previously painted segments may be covered by some the subsequent ones. Your task is counting the segme 阅读全文