Exercise 8-7 string sorting

. 1 #include <stdio.h>
 2 #include < String .h>
 . 3  
. 4  int main ( void )
 . 5  {
 . 6      char STR [ . 5 ] [ 80 ]; // a two-dimensional array holding a string 5 
. 7      int I, J ;
 . 8  
. 9      for (I = 0 ; I < . 5 ; I ++ )
 10      {
 . 11          Scanf ( " % S " , STR [I]); // input string 5 
12 is      }
 13 is  
14      for (i = 0; i < 4; i++)
15     {
16         int index = i;
17         for (j = i + 1; j < 5; j++)
18         {
19             if (strcmp(str[index], str[j]) > 0)
20             {
21                 index = j;
22             }
23         }
24         if (i != index)
25         {
26             char t[80];
27             strcpy(t, str[index]); //交换字符串
28             strcpy(str[index], str[i]);
29             strcpy(str[i], t);
30         }
31     }
32 
33     printf("After sorted:\n");
34     for (i = 0; i < 5; i++)
35     {
36         puts(str[i]);
37     }
38 
39     return 0;
40 }