987的时候B不会做，这场C不会做，感觉很接近退役了。当时想到了类似的做法，先把最少的一个用到只剩一个，然后用那一个铺满图，但是很难写，写了一个多小时也没写出来。Codeforces-989A - A Blend of Springtime - 水题Codeforces-989B - A Tide of Riverscape - 思维Codeforces-989C -...
题目链接http://codeforces.com/contest/989/problem/C题目There are four kinds of flowers in the wood, Amaranths, Begonias, Centaureas and Dianthuses.The wood can be represented by a rectangular grid of n r...
题目链接http://codeforces.com/contest/989/problem/B题目The records are expressed as a string s of characters '0', '1' and '.', where '0' denotes a low tide, '1' denotes a high tide, and '.' denotes an un...
题目链接http://codeforces.com/contest/989/problem/A题目The landscape can be expressed as a row of consecutive cells, each of which either contains a flower of colour amber or buff or canary yellow, or is...
题目链接http://poj.org/problem?id=2689题目DescriptionThe branch of mathematics called number theory is about properties of numbers. One of the areas that has captured the interest of number theoreticians...