[PAT]1009 Product of Polynomials （25 分）Java

This time, you are supposed to find

Input Specification:

Each input file contains one test case. Each case occupies 2 lines, and each line contains the information of a polynomial:

$N1N_1N1aN1a_{N_1}aN1N2N_2N2aN2a_{N_2}aN2 ... NKN_KNKaNKa_{N_K}aNK$

where $NiN_iNi and aNia_{N_i}aNi (i=1,2,⋯,Ki=1, 2, cdots , Ki=1,2,⋯,K) are the exponents and coefficients, respectively. It is given that 1≤K≤101le K le 101≤K≤10, 0≤NK<⋯<N2<N1≤10000 le N_K < cdots < N_2 < N_1 le 10000≤NK<⋯<N2<N1≤1000.$

Output Specification:

For each test case you should output the product of

Sample Input:

2 1 2.4 0 3.2
2 2 1.5 1 0.5

Sample Output:

3 3 3.6 2 6.0 1 1.6

 1 package pattest;
 2 
 3 import java.util.Scanner;
 4 
 5 /**
 6  * @Auther: Xingzheng Wang
 7  * @Date: 2019/2/18 21:38
 8  * @Description: pattest
 9  * @Version: 1.0
10  */
11 public class PAT1009 {
12     public static void main(String[] args) {
13         int k1, k2, count = 0;
14         double[] a = new double[1001];
15         double[] b = new double[2001];
16         Scanner sc = new Scanner(System.in);
17         k1 = sc.nextInt();
18         for (int i = 0; i < k1; i++) {
19             int index = sc.nextInt();
20             a[index] = sc.nextDouble();
21         }
22         k2 = sc.nextInt();
23         for (int i = 0; i < k2; i++) {
24             int index = sc.nextInt();
25             double s = sc.nextDouble();
26             for (int j = 0; j < 1001; j++) {
27                 if (a[j] != 0) {
28                     b[index + j] += s * a[j];
29                 }
30             }
31         }
32         for (int i = 0; i < 2001; i++) {
33             if (b[i] != 0)
34                 count++;
35         }
36         System.out.print(count);
37         for (int i = 2000; i >= 0; i--) {
38             if (b[i] != 0)
39                 System.out.printf(" %d %.1f", i, b[i]);
40         }
41     }
42 }