一个文件，其中数据为
abd12068ef
cf3205864lg
egi08832nnnpk
gop66896 hi
pfr52263f
ope48126pk
adc68021p6
vbg32325 4lo
...
文件行数不定，可能有好几万行，要以每行4-8位的整数为关键字进行排序，比如前8行，排序后顺序应为
egi08832nnnpk
abd12068ef
cf3205864lg
vbg32325 4lo
ope48126pk
pfr52263f
gop66896 hi
adc68021p6
我的代码如下：
#include<stdio.h>
#include "string.h"
#include "stdlib.h"
#include <malloc.h>
#define LENGTH 1000000  
#define n 100   
//void paixu(int shuju[], int shangbiao, int xiabiao);
void paixu(int shuju[], int shangbiao, int xiabiao,char str[][n]);
void main()
{
//获取文件行数
FILE *f;
char c;
//char str[LENGTH][100];
  char strr[n];
int lines = 0;//获得的文件行数;

f = fopen("test.txt", "r");

if(f == NULL)
printf("can't open test.txt to read!\n");

while((c = fgetc(f)) != EOF)
if(c == '\n')
lines++;

fclose(f);

if(c != '\n')
lines++;


printf("行数：%d\n",lines);
int m,i,j;
  char **str;
int *shuju;
char **b;
  str=(char **)malloc(lines*sizeof(char *));
  str[0]=(char *)malloc(lines*n*sizeof(char));
  b=(char **)malloc(lines*sizeof(char *));
  b[0]=(char *)malloc(lines*n*sizeof(char));
shuju= (int *)malloc(sizeof(int)*lines);

FILE *fi;
fi=fopen("test.txt","r");

if(fi==NULL)
{
printf("can't open test.txt to read!\n");
exit(0);
}
for(i=0;i<lines;i++)
{
fgets(strr,100,fi);
strcpy((char*)str[i],strr);
strncpy(b[i],str[i]+3,5);
b[i][5]=0;
shuju[i]=atoi((char*)b[i]);
  

}
fclose(fi);

  free(*str);
  free(str);
  free(*b);
  free(b);
  free(shuju);
paixu(shuju,0,lines-1,str);   
printf("排序后:\n");
for(i=0;i<lines;i++)
{

printf("%s\n ",str[i]);
}
   
}
void paixu(int shuju[], int shangbiao, int xiabiao,char str[][n])

{
 int i=shangbiao,j=xiabiao;   
 int shu=i;   
 int zhongjie;
 char bb[100];
if(shangbiao<xiabiao)
{
  while(i<j)  
  {
  for(;j>shu;j--)  
  {
  if(shuju[j]<shuju[shu])  
  {
  zhongjie=shuju[j];
  shuju[j]=shuju[shu];   
  shuju[shu]=zhongjie;
strcpy(bb,str[j]);
strcpy(str[j],str[shu]);
strcpy(str[shu],bb);

  shu=j;   
  break;  
  }
  }
  i++;   
  for(;i<shu;i++)  
  {
  if(shuju[i]>shuju[shu])
  {
  zhongjie=shuju[i];
  shuju[i]=shuju[shu];
  shuju[shu]=zhongjie;
strcpy(bb,str[i]);
strcpy(str[i],str[shu]);
strcpy(str[shu],bb);
  shu=i;  
  break;
  }
  }
  j--;  
  }
  paixu(shuju,shangbiao,shu-1,str);  
  paixu(shuju,shu+1,xiabiao,str);   
// paixu(shuju,shangbiao,shu-1);  
// paixu(shuju,shu+1,xiabiao);   
}   
}