摘要：
C. Voltage Keepsake 题目链接：http://codeforces.com/problemset/problem/801/C time limit per test 2 seconds memory limit per test 256 megabytes input standa 阅读全文
摘要：
B. Valued Keys 题目链接：http://codeforces.com/contest/801/problem/B time limit per test 2 seconds memory limit per test 256 megabytes input standard input 阅读全文