矩阵的乘法

这个程序用来实现矩阵的乘法计算，对于不同行列之间也可计算。关键在于cM和cN的选取。源码如下：

CODE:

 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include <string.h>
 4 #define MAXM 1000
 5 #define MAXN 1000
 6 
 7 /* 定义矩阵的结构体 */
 8 typedef int ElemType;
 9 typedef struct node
10 {
11     int m, n;
12     ElemType e[MAXM][MAXN];
13 }Matrix, *PMatrix;
14 
15 //
16 int Cal(PMatrix a, PMatrix b, int n, int x, int y)
17 {
18     int i;
19     int sum = 0;
20     for (i = 0; i < n; ++i)
21     {
22         sum += (a->e[x][i] * b->e[i][y]);
23     }
24     return sum;
25 }
26 
27 int main()
28 {
29     while (1)
30     {
31         
32         PMatrix a, b, c;
33         a = (PMatrix)malloc(sizeof(Matrix));
34         b = (PMatrix)malloc(sizeof(Matrix));
35         c = (PMatrix)malloc(sizeof(Matrix));
36         memset(a->e, 0, sizeof(a->e));
37         memset(b->e, 0, sizeof(b->e));
38         int i, j;
39         printf("Please input a.m and a.n:\n");
40         scanf("%d %d", &a->m, &a->n);
41         printf("Please input A:\n");
42         for (i = 0; i < a->m; ++i)
43             for (j = 0; j < a->n; ++j) scanf("%d", &a->e[i][j]);
44         printf("Please input b.m and b.n:\n");
45         scanf("%d %d", &b->m, &b->n);
46         printf("Please input B:\n");
47         for (i = 0; i < b->m; ++i)
48             for (j = 0; j < b->n; ++j) scanf("%d", &b->e[i][j]);
49 
50         int cM = a->m;
51         int cN = b->n;
52         printf("\nA * B :\n");
53         for (i = 0; i < cM; ++i)
54         {
55             printf("\t");
56             for (j = 0; j < cN; ++j)
57             {
58                 c->e[i][j] = Cal(a, b, cM, i, j);
59                 printf("%d ", c->e[i][j]);
60             }
61             printf("\n");
62         }
63     }
64     return 0;
65 }