se.moevm.info

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== qsort ==

<code c++>
// Programming 1. Sample at 2016-11-24-14-34.16

#include <stdio.h> #include <stdlib.h>

int data[10] = {32387241,2,2,4,5,9,55,3,77,3};

int compare(const void *a, const void *b) {

char valuea = *((char*)a);
char valueb = *((char*)b);

printf(“comparing %d %d\n”,valuea,valueb); return valuea-valueb; } int compare_r(const void *a, const void *b) { char valuea = *((char*)a); char valueb = *((char*)b); printf(“comparing %d %d\n”,valuea,valueb);

return valueb-valuea;

}

void print_data() {

char *ptr = (char*)data;
for(int i=0;i<40;i++)
{
  printf("%d ",ptr[i]);
}
printf("\n");

}

int main(/*int c, char **v */) {

print_data();   
qsort(data,40,sizeof(char),compare);
print_data();   
qsort(data,40,sizeof(char),compare_r);
print_data();   

return 0;

}

</code>