C語言 將字串按照指定字元分離並且反轉(三級指標)列子

gaopengtttt發表於2017-01-03
C語言字串字元指標
C語言 將字串分離並且反轉(三級指標)


本程式完成功能
1、將輸入的字串按照指定字元分離為子字串
2、將子字串進行反轉
使用方法
在棧空間分配一個三級指標，指向堆記憶體空間的指標陣列的位置，每個指標陣列成員又指向一個字串，必須明確如下的
記憶體四區圖這裡只畫最為複雜的分離字元函式，而不畫反轉函式，因為反轉函式模型非常簡單，而且畫太多太麻煩。
在圖中反應出strsplrev中的int len和 char** str為輸出變數，也就是說str用來接受malloc出來的二級指標的值，那麼我們應該
將三級指標傳入，另外argv輸入的字串放到了全域性區，這個區域是不能更改的，所以用一個堆instr將他接收過來，這也是典
型的場景下圖(圖中將i m p3個棧變數放到了一起)，重點在於堆中的記憶體理解問題。

程式輸出如下：
gaopeng@bogon:~/stepup/3rd$ ./splitstr oracle-mysql-mongodb -
----len is 3
oracle
mysql
mongodb
----reverse now!
elcaro
lqsym
bdognom
----free mem!

四區圖如下：





最後給出實現程式碼：

點選(此處)摺疊或開啟

  1. 介面標頭檔案：
  2. /*************************************************************************
  3.     > File Name: fun.h
  4.     > Author: gaopeng QQ:22389860 all right reserved
  5.     > Mail: gaopp_200217@163.com
  6.     > Created Time: Tue 24 Jan 2017 03:50:07 PM CST
  7.  ************************************************************************/


  10. int strsplt(const char* instrt/*in*/,const char* spchar/*in*/,char** *outp/*out*/,int* len/*out*/);
  11. int strrevs(char* instrt/*in out*/);
  12. int strsplrev(char *p1,char *p2);

  14. 介面實現檔案：
  15. /*************************************************************************
  16.   > File Name: fun.c
  17.   > Author: gaopeng QQ:22389860 all right reserved
  18.   > Mail: gaopp_200217@163.com
  19.   > Created Time: Tue 24 Jan 2017 02:02:20 PM CST
  20.  ************************************************************************/

  22. #include<stdio.h>
  23. #include<stdlib.h>
  24. #include<string.h>

  26. int mfree(char** *freep,int len)
  27. {
  28.         int i=0;
  29.         if(*freep==NULL)
  30.         {
  31.                 return 0;
  32.         }
  33.         for(i=0;i<len;i++)
  34.         {
  35.                 if(*(*freep+i) !=NULL)
  36.                 {
  37.                         printf("%d ",i);
  38.                         free(*(*freep+i));
  39.                         *(*freep+i)=NULL;
  40.                 }
  41.         }
  42.         free(*freep);
  43.         freep = NULL;
  44.         return 0;
  45. }


  48. /*-1 flase 0 ture*/
  49. int strsplt( char* instr,const char* spchar,char** *outp,int* len )
  50. {
  51.         char** temp=NULL;
  52.         int i=0,m=0,p=0;
  53.         int templen=0;
  54.         char* tempsrc=NULL;

  56.         if(instr==NULL||spchar==NULL||outp==NULL||len==NULL)
  57.         {
  58.                 printf("strsplt error:instr==NULL||spchar==NULL||outp==NULL||len==NULL\n");
  59.                 goto err;
  60.         }
  61.         p = 1;
  62.         for(i=0;i<strlen(instr);i++)
  63.         {
  64.                 if(instr[i]==spchar[0])
  65.                 {
  66.                         if (i == strlen(instr)-1)
  67.                         {
  68.                                 printf("strsplt error:last char is spchar \n");
  69.                                 goto err;
  70.                         }
  71.                         if(instr[i+1]==spchar[0])
  72.                         {
  73.                                 printf("strsplt error:two or more spchar \n");
  74.                                 goto err;
  75.                         }

  77.                         p++;
  78.                 }
  79.         }

  81.         *len = p;
  82.         templen = p;//used mfree fun

  84.         if((temp=(char**)calloc(1,p*sizeof(char*)))==NULL)
  85.         {
  86.                 printf("strsplt error:mem calloc error\n");
  87.                 goto err;
  88.         }
  89.         *outp=temp;
  90.         for(i=0,p=0,m=0;i<strlen(instr);i++)//i is step p is step of pointer m is len of substr
  91.         {
  92.                 if(instr[i]==spchar[0])
  93.                 {
  94.                         tempsrc=instr+m;
  95.                         if( (*(temp+p)= (char*)calloc(1,i-m+1))==NULL)
  96.                         {
  97.                                 printf("strsplt error:mem calloc error\n");
  98.                                 goto err;
  99.                         }
  100.                         strncpy(*(temp+p),tempsrc,i-m);
  101.                         p++;
  102.                         m=i+1;
  103.                 }
  104.         }
  105.         //last copy
  106.         tempsrc=instr+m;
  107.         if( (*(temp+p)= (char*)calloc(1,i-m+1)) == NULL)
  108.         {
  109.                 printf("strsplt error:mem calloc error\n");
  110.                 goto err;
  111.         }
  112.         strncpy(*(temp+p),tempsrc,i-m);
  113.         return 0;

  115.         err:
  116.         mfree(&temp,templen);
  117.         return -1;

  119. }

  121. /* -1 false 0 true*/
  122. int strrevs(char* instrt)
  123. {
  124.         int templ=0;
  125.         int i=0,j=0;
  126.         char tempc=0;
  127.         templ = strlen(instrt);
  128.         if(instrt == NULL || templ==0)
  129.         {
  130.                 printf("strrevs error:instrt == NULL || templ=0\n");
  131.                 return -1;
  132.         }
  133.         for(i=0,j=templ-1;i<j;i++,j--)
  134.         {
  135.                 tempc=instrt[j];
  136.                 instrt[j]=instrt[i];
  137.                 instrt[i]=tempc;
  138.         }
  139.         return 0;
  140. }

  142. int strsplrev(char *p1,char *p2)
  143. {

  145.         char* *str=NULL;
  146.         int slen=0;
  147.         int i=0;

  149.         if(strsplt(p1,p2,&str,&slen) == 0)
  150.         {
  151.                 printf("----len is %d\n",slen);
  152.                 for(i=0;i<slen;i++)
  153.                 {
  154.                         printf("%s\n",*(str+i));
  155.                 }
  156.         }
  157.         else
  158.         {
  159.                 printf("error!\n");
  160.                 return 3;
  161.         }

  163.         printf("----reverse now!\n");
  164.         for(i=0;i<slen;i++)
  165.         {

  167.                 if(strrevs(*(str+i)) !=0)
  168.                 {

  170.                         printf("error!\n");
  171.                         return 4;
  172.                 }
  173.                 else
  174.                 {

  176.                         printf("%s\n",*(str+i));
  177.                 }
  178.         }
  179.         printf("----free mem!\n");
  180.         mfree(&str,slen);
  181.         return 0;
  182. }

  184. main呼叫檔案：
  185. /*************************************************************************
  186.   > File Name: main.c
  187.   > Author: gaopeng QQ:22389860 all right reserved
  188.   > Mail: gaopp_200217@163.com
  189.   > Created Time: Tue 24 Jan 2017 02:02:09 PM CST
  190.  ************************************************************************/

  192. #include<stdio.h>
  193. #include<stdlib.h>
  194. #include<string.h>
  195. #include"fun.h"


  198. int main(int argc,char* argv[])
  199. {

  201.         if(argc!=3||strcmp(argv[1],"--help")==0)
  202.         {
  203.                 printf("usage ./tool str spchar \n");
  204.                 return 1;
  205.         }

  207.         if(strlen(argv[2]) !=1)
  208.         {
  209.                 printf("par2 split char only one char\n");
  210.                 return 2;
  211.         }

  213.         strsplrev(argv[1],argv[2]);
  214.         return 0;


  217. }







來自 “ ITPUB部落格 ” ，連結：http://blog.itpub.net/7728585/viewspace-2131812/，如需轉載，請註明出處，否則將追究法律責任。

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