CF 1003D Coins and Queries【位运算/硬币值都为2的幂/贪心】-白红宇

CF 1003D Coins and Queries【位运算/硬币值都为2的幂/贪心】

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发布时间：2019-06-14

本文共 2965 字，大约阅读时间需要 9 分钟。

Polycarp has n coins, the value of the i-th coin is ai. It is guaranteed that all the values are integer powers of 2 (i.e. ai=2d for some non-negative integer number d).

Polycarp wants to know answers on q queries. The j-th query is described as integer number bj. The answer to the query is the minimum number of coins that is necessary to obtain the value bj using some subset of coins (Polycarp can use only coins he has). If Polycarp can't obtain the value bj, the answer to the j-th query is -1.

The queries are independent (the answer on the query doesn't affect Polycarp's coins).

Input

The first line of the input contains two integers n and q (1≤n,q≤2⋅105) — the number of coins and the number of queries.

The second line of the input contains n integers a1,a2,…,an — values of coins (1≤ai≤2⋅109). It is guaranteed that all ai are integer powers of 2 (i.e. ai=2d for some non-negative integer number d).

The next q lines contain one integer each. The j-th line contains one integer bj — the value of the j-th query (1≤bj≤109).

Output

Print q integers ansj. The j-th integer must be equal to the answer on the j-th query. If Polycarp can't obtain the value bj the answer to the j-th query is -1.

Example

Input

5 4

2 4 8 2 4

Output

-1

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转载于:https://www.cnblogs.com/Roni-i/p/9348667.html

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