B. Shopping 题目连接: http://www.codeforces.com/contest/665/problem/B Description Ayush is a cashier at the shopping center. Recently his department has started a ''click and collect" service which allows users to shop online. The store contains k items.…
F. Four Divisors 题目连接: http://www.codeforces.com/contest/665/problem/F Description If an integer a is divisible by another integer b, then b is called the divisor of a. For example: 12 has positive 6 divisors. They are 1, 2, 3, 4, 6 and 12. Let's def…
E. Beautiful Subarrays 题目连接: http://www.codeforces.com/contest/665/problem/E Description One day, ZS the Coder wrote down an array of integers a with elements a1, a2, ..., an. A subarray of the array a is a sequence al, al + 1, ..., ar for so…
A. Buses Between Cities 题目连接: http://www.codeforces.com/contest/665/problem/A Description Buses run between the cities A and B, the first one is at 05:00 AM and the last one departs not later than at 11:59 PM. A bus from the city A departs every a mi…
D. Simple Subset 题目连接: http://www.codeforces.com/contest/665/problem/D Description A tuple of positive integers {x1, x2, ..., xk} is called simple if for all pairs of positive integers (i, j) (1 ≤ i < j ≤ k), xi + xj is a prime. You are given a…
C. Simple Strings 题目连接: http://www.codeforces.com/contest/665/problem/C Description zscoder loves simple strings! A string t is called simple if every pair of adjacent characters are distinct. For example ab, aba, zscoder are simple whereas aa, add a…
