PAT甲级——A1037 Magic Coupon

The magic shop in Mars is offering some magic coupons. Each coupon has an integer N printed on it, meaning that when you use this coupon with a product, you may get N times the value of that product back! What is more, the shop also offers some bonus product for free. However, if you apply a coupon with a positive N to this bonus product, you will have to pay the shop N times the value of the bonus product... but hey, magically, they have some coupons with negative N's!

For example, given a set of coupons { 1 2 4 − }, and a set of product values { 7 6 − − } (in Mars dollars M$) where a negative value corresponds to a bonus product. You can apply coupon 3 (with N being 4) to product 1 (with value M$7) to get M$28 back; coupon 2 to product 2 to get M$12 back; and coupon 4 to product 4 to get M$3 back. On the other hand, if you apply coupon 3 to product 4, you will have to pay M$12 to the shop.

Each coupon and each product may be selected at most once. Your task is to get as much money back as possible.

Input Specification:

Each input file contains one test case. For each case, the first line contains the number of coupons NC​​, followed by a line with NC​​ coupon integers. Then the next line contains the number of products NP​​, followed by a line with NP​​ product values. Here 1, and it is guaranteed that all the numbers will not exceed 230​​.

Output Specification:

For each test case, simply print in a line the maximum amount of money you can get back.

Sample Input:

4
1 2 4 -1
4
7 6 -2 -3

Sample Output:

43


 1 #include <iostream>
 2 #include <vector>
 3 #include <string>
 4 #include <algorithm>
 5 using namespace std;
 6 //牛客这道题涉及数相乘会int溢出,而PAT没有,所以pat使用int类型就可以,而牛客需要使用longlong型
 7 long long Nc, Np, p = 0, q = 0, a, res = 0;
 8 int main()
 9 {
10     cin >> Nc;
11     vector<long>Vc, Vp;
12     for (int i = 0; i < Nc; ++i)
13     {
14         cin >> a;
15         Vc.push_back(a);
16     }
17     cin >> Np;
18     for (int i = 0; i < Np; ++i)
19     {
20         cin >> a;
21         Vp.push_back(a);
22     }
23     sort(Vc.begin(), Vc.end(), [](long long u, long long v) {return u < v; });
24     sort(Vp.begin(), Vp.end(), [](long long u, long long v) {return u < v; });
25     while (p < Nc&&q < Np&&Vc[p] < 0 && Vp[q] < 0)//先负数相乘
26     {
27         res += Vc[p] * Vp[q];
28         ++p;
29         ++q;
30     }
31     p = Nc - 1;
32     q = Np - 1;
33     while (p >= 0 & q >= 0 && Vc[p] > 0 && Vp[q] > 0)//正数从后开始乘
34     {
35         res += Vc[p] * Vp[q];
36         --p;
37         --q;
38     }
39     cout << res << endl;
40     return 0;
41 }
原文地址:https://www.cnblogs.com/zzw1024/p/11256891.html