摘要：835D：http://codeforces.com/problemset/problem/835/D emmmm不太会，附大佬代码 阅读全文

摘要：839C：http://codeforces.com/problemset/problem/835/C 题意：给出星星的个数，最大亮度（每时间+1，亮度+1，但不超过最大亮度），观测者观测的次数及时刻， 求观测时刻矩形内星星的亮度和。 这里要用到一个三维数组，一维记录时间，另外两维记录时间t时坐标（ 阅读全文

摘要：B. Godsend Leha somehow found an array consisting of n integers. Looking at it, he came up with a task. Two players play the game on the array. Player 阅读全文

摘要：A. Generous Kefa One day Kefa found n baloons. For convenience, we denote color of i-th baloon as si — lowercase letter of the Latin alphabet. Also Ke 阅读全文