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  1. #include <stdio.h>
  2. #include <stdlib.h>
  3.  
  4. #define SIZE 5
  5.  
  6. void print(int **arr) {
  7.     int i;
  8.     for (i = 0; i < SIZE; ++i) {
  9.         printf("%d ", arr[i][0]);
  10.         printf("%d\n", arr[i][1]);
  11.     }
  12. }
  13.  
  14. int compare(const void *lhs, const void *rhs)
  15. {
  16.     const int *l = *(const int**)lhs;
  17.     const int *r = *(const int**)rhs;
  18.     if (l[0] > r[0]) 
  19.         return 1;
  20.     else if (l[0] < r[0])
  21.         return -1;
  22.     else {
  23.         if (l[1] > r[1])
  24.             return 1;
  25.         else if (l[1] < r[1])
  26.             return -1;
  27.         else
  28.             return 0;
  29.     }
  30. }
  31.  
  32. int main()
  33. {
  34.     int **arr = (int**)malloc(SIZE*sizeof(int*));
  35.     int *tmp = (int*)malloc(SIZE*2*sizeof(int));
  36.     int i;
  37.  
  38.     for (i = 0; i < SIZE; ++i) {
  39.         arr[i] = &tmp[i*2];
  40.     }
  41.     arr[0][0] = 2;
  42.     arr[0][1] = 2;
  43.  
  44.     arr[1][0] = 2;
  45.     arr[1][1] = 1;
  46.  
  47.     arr[2][0] = 1;
  48.     arr[2][1] = 1;
  49.  
  50.     arr[3][0] = 1;
  51.     arr[3][1] = 0;
  52.  
  53.     arr[4][0] = 0;
  54.     arr[4][1] = 0;
  55.  
  56.     print(arr);
  57.     qsort(arr, SIZE, sizeof(int*), compare);
  58.     printf("\n");
  59.     print(arr);
  60.  
  61.     free(tmp);
  62.     free(arr);
  63.  
  64.     return 0;
  65.  
  66. }
  67.  
  68.  
Success #stdin #stdout 0s 2424KB
comments (?)
stdin 
Standard input is empty
stdout 
2 2
2 1
1 1
1 0
0 0

0 0
1 0
1 1
2 1
2 2
https://ideone.com/VWhVUs
language:
C (gcc 8.3)
created:
11 years ago
visibility:
public

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