HackerRank C Solution - Sorting Array of Strings

The output consists of the strings sorted according to the four comparsion functions in the order mentioned in code

1. #include <stdio.h>
2. #include <stdlib.h>
3. #include <string.h>
4. int lexicographic_sort(const char* a, const char* b){
5. return strcmp(a, b) > 0;
6. }
8. int lexicographic_sort_reverse(const char* a, const char* b){
9. return strcmp(a, b) <= 0;
10. }
12. int sort_by_number_of_distinct_characters(const char* a, const char* b){
13. int c1 = 0, c2 = 0;
14. int hsh1[26] = {0}, hsh2[26] = {0};
15. int n1 = strlen(a);
16. int n2 = strlen(b);
18. for(int i = 0; i < n1; i++){
19. hsh1[a[i] - 'a'] = 1;
20. }
22. for(int i = 0; i < n2; i++){
23. hsh2[b[i] - 'a'] = 1;
24. }
26. for(int i = 0; i < 26; i++){
27. if(hsh1[i])
28. c1++;
29. if(hsh2[i])
30. c2++;
31. }
32. if( c1 != c2)
33. return c1 > c2;
34. else
35. return strcmp(a, b) > 0;
37. }
39. int sort_by_length(const char* a, const char* b){
40. if(strlen(a) != strlen(b))
41. return strlen(a) > strlen(b);
42. else
43. return strcmp(a, b) > 0;
44. }
46. void string_sort(char** arr,const int len,int (*cmp_func)(const char* a, const char* b)){
47. for(int i = 1; i < len; i++){
48. int j = i;
49. char* p = arr[i];
50. while(j > 0){
51. if((*cmp_func)(arr[j-1],p) > 0 )
52. arr[j] = arr[j-1];
53. else
54. break;
55. j--;
56. }
57. arr[j] = p;
58. }
59. }
60. }
63. int main()
64. {
65. int n;
66. scanf("%d", &n);
68. char** arr;
69. arr = (char**)malloc(n * sizeof(char*));
71. for(int i = 0; i < n; i++){
72. *(arr + i) = malloc(1024 * sizeof(char));
73. scanf("%s", *(arr + i));
74. *(arr + i) = realloc(*(arr + i), strlen(*(arr + i)) + 1);
75. }
77. string_sort(arr, n, lexicographic_sort);
78. for(int i = 0; i < n; i++)
79. printf("%s\n", arr[i]);
80. printf("\n");
82. string_sort(arr, n, lexicographic_sort_reverse);
83. for(int i = 0; i < n; i++)
84. printf("%s\n", arr[i]);
85. printf("\n");
87. string_sort(arr, n, sort_by_length);
88. for(int i = 0; i < n; i++)
89. printf("%s\n", arr[i]);
90. printf("\n");
92. string_sort(arr, n, sort_by_number_of_distinct_characters);
93. for(int i = 0; i < n; i++)
94. printf("%s\n", arr[i]);
95. printf("\n");
96. }