数组练习题

 1 public int[][] matrixMulti(int[][]a, int[][]b){
 2         int[][] answer = new int[a.length][b[0].length];
 3 
 4         if (a[0].length != b.length)
 5         {
 6             System.out.println("这两个矩阵不能相乘！");
 7             return answer;
 8         }
 9         
10         
11         for (int[] x: answer )
12         {
13             for (int y: x )
14             {
15                 y = 0;
16             }
17         }
18 
19         for (int i=0;i<a.length ;i++ )    
20         {
21             for (int j=0;j<b[i].length ;j++ )    
22             {    
23                  for (int k = 0;k < b[i].length ; k++ )    
24                  {
25                      
26                      answer[i][j] = answer[i][j] + a[i][k] *  b[k][i];
27                  }    
28             }
29         }
30         return answer;
31     }