海明码计算器

当你学习了海明码（汉明码）的时候，有没有想过自己来写一个程序去实现这个奇怪的东西呢？可能很多人还不是很清楚这个海明码到底是什么东西，那就让我们来用我们的智慧来打败那个怪叔叔吧！Fighting。。。

1. 海明码的生成：

CODE：

 1 #include <stdio.h>
 2 #include <string.h>
 3 #include <math.h>
 4 
 5 #define MAX 100 // The maximum length of binary string
 6 
 7 /* cal int from char */
 8 int CalCharToInt(char c)
 9 {
10     return (c - '0');
11 }
12 
13 /* cal r */
14 int Cal_R(int k)
15 {
16     int r;
17     for (r = 0; pow(2.0, r) < k + r + 1; ++r)
18     { } // do nothing
19 
20     return r;
21 }
22 
23 int main()
24 {
25     int k, r;
26     char rein[MAX];
27     while (1)
28     {
29         printf("k = ");
30         scanf("%d", &k);
31         getchar();
32         printf("Information Code: ");
33         fgets(rein, MAX, stdin);
34         r = Cal_R(k);
35         //printf("k = %d, r = %d, s = %s\n", k, r, rein);
36 
37         int inform_H[MAX], r_H[MAX];
38         memset(inform_H, 0, sizeof(inform_H));
39         memset(r_H, 0, sizeof(r_H));
40         int i, t, m;
41         
42         for (i = 1, t = 0, m = 1; i < k + r; ++i) // save rein[] to a int array rein_H[]
43         {
44             if (i == (int)pow(2.0, (m-1))) // location r_H[i+1] data is 0
45             {
46                 inform_H[i] = 0;
47                 ++m;
48                 // printf("insert %d\n", i);
49             }
50             else
51             {
52                 inform_H[i] = CalCharToInt(rein[t]);
53                 ++t;
54             }
55         }
56 
57         int sum; // save sum from r_H[i]
58         int temp;
59         for (i = 1; i <= r; ++i) // cal the real value of r_H[i]
60         {
61             temp = (int)pow(2.0, i-1);
62             for (t = 1, sum = 0; t <= k + r; ++t)
63             {
64                 if ((t/temp)%2) // if this location is right
65                 {
66                     sum += inform_H[t];
67                 }
68             }
69             r_H[i] = sum % 2; // a even number check-up
70             // printf("%d\n", r_H[i]);
71         }
72         
73         for (i = 1, t = 1; i <= k + r; ++i)
74         {
75             if (i == (int)pow(2.0, t-1))
76             {
77                 inform_H[i] = r_H[t]; // change to right at the right location
78                 ++t;
79             }
80         }
81 
82         printf("Hamming Code: ");
83         for (i = 1; i <= k + r; ++i)
84         {
85             printf("%d", inform_H[i]);
86         }
87         printf("\n\n");
88     }
89     return 0;
90 }

 

2. 海明码的接收：

CODE：

 1 #include <stdio.h>
 2 #include <string.h>
 3 #include <math.h>
 4 
 5 #define MAX 100 // The maximum length of binary string
 6 
 7 /* cal int from char */
 8 int CalCharToInt(char c)
 9 {
10     return (c - '0');
11 }
12 
13 /* cal r */
14 int Cal_R(int k)
15 {
16     int r;
17     for (r = 0; pow(2.0, r) < k + r + 1; ++r)
18     { } // do nothing
19 
20     return r;
21 }
22 
23 int main()
24 {
25     int k, r;
26     char rein[MAX];
27     while (1)
28     {
29         printf("k = ");
30         scanf("%d", &k);
31         getchar();
32         printf("Receive Code: ");
33         fgets(rein, MAX, stdin);
34         r = Cal_R(k);
35         //printf("k = %d, r = %d, s = %s\n", k, r, rein);
36 
37         int receive_H[MAX], r_H[MAX];
38         memset(receive_H, 0, sizeof(receive_H));
39         memset(r_H, 0, sizeof(r_H));
40         int i, t, m;
41         int err;
42         
43         for (i = 1; i <= k + r; ++i) // save rein[] to a int array rein_H[]
44         {
45             receive_H[i] = CalCharToInt(rein[i-1]);
46         }
47 
48         int sum; // save sum from r_H[i]
49         int temp;
50         for (i = 1; i <= r; ++i) // cal the real value of r_H[i]
51         {
52             temp = (int)pow(2.0, i-1);
53             for (t = 1, sum = 0; t <= k + r; ++t)
54             {
55                 if ((t/temp)%2) // if this location is right
56                 {
57                     sum += receive_H[t];
58                 }
59             }
60             r_H[i] = sum % 2; // a even number check-up
61             // printf("%d\n", r_H[i]);
62         }
63 
64         //printf("%d,%d,%d,%d\n", r_H[1], r_H[2], r_H[3], r_H[4]);
65         
66         for (i = 1, err = 0; i <= r; ++i) // cal err
67         {
68             err += ( (r_H[i]) * (int)pow(2.0, (i-1)) );
69         }
70         printf("err = %d\n", err);
71 
72         receive_H[err] = (receive_H[err] + 1) % 2;
73 
74         printf("Information Code: ");
75         for (i = 1, t = 0; i <= k + r; ++i)
76         {
77             temp = (int)pow(2.0, (t));
78             if (temp != i) // remove redundancy code
79             {
80                 printf("%d", receive_H[i]);
81                 //printf("\n%d", temp);
82             }
83             else ++t;
84         }
85         printf("\n\n");
86     }
87     return 0;
88 }