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  1. #include <stdio.h>
  2. #include <stdlib.h>
  3.  
  4. void pp(int *a, int r, int c,const char *msg)
  5. {
  6.   int i,j;
  7.   printf("%s\n", msg);
  8.   for ( i = 0; i < r; ++i) {
  9.     for ( j = 0; j < c; ++j) {
  10.       printf("%4d", *a++);
  11.     }
  12.     puts("");
  13.   }
  14.   puts("");
  15. }
  16.  
  17. int
  18. main()
  19. {
  20.   int             a[][2] = {
  21.     {1, 2},
  22.     {3, 4},
  23.     {5, 6}
  24.   };
  25.   int             b[][3] = {
  26.     {1, 2, 4},
  27.     {3, 6, 9}
  28.   };
  29.  
  30.   int row = sizeof(a) / sizeof(a[0]);
  31.   int col = sizeof(a[0]) / sizeof(int);
  32.   int *c = (int *)malloc(sizeof(int) * row * col);
  33.   int i;
  34.   for (i = 0; i < row * row; ++i) {
  35.     int w1 = i / row * col, w2 = i % row;
  36.     c[i] += *(*a + w1) * *(*b + w2);
  37.     w1 += col;
  38.     w2 += row;
  39.     c[i] += *(*a + w1) * *(*b + w2);
  40.   }
  41.  
  42.   pp(*a,3,2,"行列xを表示");
  43.   pp(*b,2,3,"行列yを表示");
  44.   pp(c,3,3,"行列xとyの積を表示");
  45.  
  46.   return 0;
  47. }
Success #stdin #stdout 0.02s 1852KB
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stdin
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Standard input is empty
stdout
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行列xを表示
   1   2
   3   4
   5   6

行列yを表示
   1   2   4
   3   6   9

行列xとyの積を表示
  10  20  31
  18  36  57
10717541492143643435-1079704844
https://ideone.com/8Nn4Gq
language:
C (gcc 8.3)
created:
12 years ago
visibility:
secret

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