D. Dividing Kingdom II 题目连接: http://www.codeforces.com/contest/687/problem/D Description Long time ago, there was a great kingdom and it was being ruled by The Great Arya and Pari The Great. These two had some problems about the numbers they like, so…

D. Remainders Game 题目连接: http://www.codeforces.com/contest/688/problem/D Description Today Pari and Arya are playing a game called Remainders. Pari chooses two positive integer x and k, and tells Arya k but not x. Arya have to find the value . There…

C. NP-Hard Problem 题目连接: http://www.codeforces.com/contest/688/problem/C Description Recently, Pari and Arya did some research about NP-Hard problems and they found the minimum vertex cover problem very interesting. Suppose the graph G is given. Subs…

B. Lovely Palindromes 题目连接: http://www.codeforces.com/contest/688/problem/B Description Pari has a friend who loves palindrome numbers. A palindrome number is a number that reads the same forward or backward. For example 12321, 100001 and 1 are palin…

A. Opponents 题目连接: http://www.codeforces.com/contest/688/problem/A Description Arya has n opponents in the school. Each day he will fight with all opponents who are present this day. His opponents have some fighting plan that guarantees they will win…

题目链接:http://codeforces.com/problemset/problem/687/A 题意:给出一个n个点m条边的图,分别将每条边连接的两个点放到两个集合中,输出两个集合中的点,若不可能则输出-1: 思路:通过画图我们不难发现,图中没有出现长度为奇数的环则是可行的,反之则是不行的． 对于这点我们可以直接用dfs搜索+染色,对于当前标记为1的点,我们将其所有儿子标记为2, 对于当前标记为2的点,将其所有儿子标记为1,若出现某个节点的标记与其儿子相同,则有长度为奇数的环. 代码:…

D. Dividing Kingdom II   Long time ago, there was a great kingdom and it was being ruled by The Great Arya and Pari The Great. These two had some problems about the numbers they like, so they decided to divide the great kingdom between themselves. Th…

E. The Values You Can Make     Pari wants to buy an expensive chocolate from Arya. She has n coins, the value of the i-th coin is ci. The price of the chocolate is k, so Pari will take a subset of her coins with sum equal to k and give it to Arya. Lo…

每次AB秒出 到了C难度陡然上升...翻译都弄不懂... C 给出一张图 找出两个点的覆盖集(覆盖集是指这图中每条边都有至少一个点在这个点集里面) 并且两个点集没有交集 英文很难看懂...就是二分图的判定 看看这张图是不是二分图 输出两边的点 不是二分图输出-1 坑点是这是special judge 但是题目没说 每个联通块都要进行一次bfs 那些独立点可以不输出也可以随意分配 D 给出k与n个数ci 我们知道一个未知的数x%ci的数 问能不能求出x%k的数 可以利用中国剩余定理来解 如果我们知…

题目链接: 题目 E. The Values You Can Make time limit per test:2 seconds memory limit per test:256 megabytes 问题描述 Pari wants to buy an expensive chocolate from Arya. She has n coins, the value of the i-th coin is ci. The price of the chocolate is k, so Pari…