+ 1

Anyone explain this code??

#include <stdio.h> #include <stdlib.h> int compare (const void *, const void *); int main() { int arr[5] = {52, 23, 56, 19, 4}; int num, width, i; num = sizeof(arr)/sizeof(arr[0]); width = sizeof(arr[0]); qsort((void *)arr, num, width, compare); for (i = 0; i < 5; i++) printf("%d ", arr[ i ]); return 0; } int compare (const void *elem1, const void *elem2) { if ((*(int *)elem1) == (*(int *)elem2)) return 0; else if ((*(int *)elem1) < (*(int *)elem2)) return -1; else return 1; }

30th Jan 2019, 8:03 AM
Selvarajah Kesavan
Selvarajah Kesavan - avatar
4 Respostas
+ 4
int main() { int arr[5] = {52, 23, 56, 19, 4}; int num, width, i; // calculate number of array elements num = sizeof(arr)/sizeof(arr[0]); // measure size of a single array element width = sizeof(arr[0]); // sort the array, using the algorithm // implemented in compare function // Reference: // https://en.cppreference.com/w/c/algorithm/qsort qsort((void *)arr, num, width, compare); // display sorted array contents for (i = 0; i < 5; i++) printf("%d ", arr[ i ]); return 0; } // sort function that supplies a value // used by qsort to decide whether // <elem1> was less, equal, or greater // compared to <elem2> int compare (const void *elem1, const void *elem2) { if ((*(int *)elem1) == (*(int *)elem2)) return 0; // return 0 if <elem1> equals <elem2> else if ((*(int *)elem1) < (*(int *)elem2)) return -1; // return -1 if <elem1> is less than <elem2> else return 1; // return 1 if <elem1> is greater than <elem2> }
30th Jan 2019, 9:32 AM
Ipang
+ 3
You're welcome, glad if it helps 👍
30th Jan 2019, 3:16 PM
Ipang
+ 2
This sorts the array arr and prints it.
30th Jan 2019, 8:51 AM
Zen
Zen - avatar
+ 1
Thankyou for the explanation Ipang
30th Jan 2019, 3:12 PM
Selvarajah Kesavan
Selvarajah Kesavan - avatar