Qsort Inductive Learning (C language version)

Reference: https://www.cnblogs.com/ForeverJoker/archive/2013/05/25/qsort-sort.html

Included in <stdlib.h>

Int (*CMP) (const void *,const void *);

Qsort (*s, N, sizeof (s[0]), CMP);

Contains 4 parameters, the first incoming position, the second sort amount, the third individual size, and the fourth sort method

Sorting an array

int type :

< Span class= "hljs-reserved" > int CMP ( const void *a, const void *b) {

< Span class= "hljs-reserved" ><　　　　　　Span class= "Hljs-keyword" > return * (int*) A-* (int*) b; < Span class= "hljs-reserved" >< Span class= "Hljs-keyword" >< Span class= "Hljs-keyword" >//from small to large sort

　　　　　　 return * (int *) b-* (int *) A; Sort from large to small}

The return value of the CMP function, <0 (no permutation), >0 (for displacement), 0 (no permutation).

Double type:

　　　　INT cmp (const void * A, const void * b) {

< Span class= "hljs-reserved" >< Span class= "Hljs-keyword" > Return ((* (* (double*) A-* (double*) b> 0)? 1:-< span class= "Hljs-number" >1);}

< Span class= "hljs-reserved" >< Span class= "Hljs-keyword" >< Span class= "Hljs-keyword" >char:

< Span class= "hljs-reserved" >< Span class= "Hljs-keyword" >< Span class= "Hljs-keyword" > Return (* (char *) A-* (char *) b)

< Span class= "hljs-reserved" >< Span class= "Hljs-keyword" >< Span class= "Hljs-keyword" >struct type:

< Span class= "hljs-reserved" >< Span class= "Hljs-keyword" >< Span class= "Hljs-keyword" > TBD

< Span class= "hljs-reserved" >< Span class= "Hljs-keyword" >< Span class= "Hljs-keyword" >char s[][] Type:

< Span class= "hljs-reserved" >< Span class= "Hljs-keyword" >< Span class= "Hljs-keyword" > int cmp (const void *a, const void *b) {

< Span class= "Hljs-keyword" >< Span class= "Hljs-keyword" >< Span class= "Hljs-number" > return (strcmp ((char*) A, (char*) b)); }

Qsort Inductive Learning (C language version)