B"You play a strategic video game (yeah, we ran out of good problem legends). In this game you control a large army, and your goal is to conquer n castles of your opponent. Let's describe the game process in detail. Initially you control an army of k warriors. Your enemy controls n castles; to conquer the i -th castle, you need at least a_i warriors (you are so good at this game that you don't lose any warriors while taking over a castle, so your army stays the same after the fight). After you take control over a castle, you recruit new warriors into your army -- formally, after you capture the i -th castle, b_i warriors join your army. Furthermore, after capturing a castle (or later) you can defend it: if you leave at least one warrior in a castle, this castle is considered defended. Each castle has an importance parameter c_i , and your total score is the sum of importance values over all defended castles. There are two ways to defend a castle: Obviously, when you order your warrior to defend some castle, he leaves your army. You capture the castles in fixed order: you have to capture the first one, then the second one, and so on. After you capture the castle i (but only before capturing castle i + 1 ) you may recruit new warriors from castle i , leave a warrior to defend castle i , and use any number of portals leading from castle i to other castles having smaller numbers. As soon as you capture the next castle, these actions for castle i won't be available to you. If, during some moment in the game, you don't have enough warriors to capture the next castle, you lose. Your goal is to maximize the sum of importance values over all defended castles (note that you may hire new warriors in the last castle, defend it and use portals leading from it even after you capture it -- your score will be calculated afterwards). Can you determine an optimal strategy of capturing and defendin"...