#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define SIZE 269
typedef unsigned char BYTE ;
 
typedef struct _IP {
 BYTE seg[4];
 struct _IP *next;
}IP;
 
int main()
{
 FILE *fp1,*fp2;
 int i, found,s,j;
 char c[100];
 IP *pip, *ptem, *pfind, *judge;
 BYTE tem_ip[4];
 pip = (IP *)malloc(sizeof(IP));
 pip->next = pip;

if((fp1=fopen("ip1","r"))==NULL)
     {
         printf("cannot open infile\n");
         exit(0);
     }
     if((fp2=fopen("route","w"))==NULL)
     {
         printf("cannot open outfile\n");
         exit(0);
     }

   for(s=1;s<=SIZE;s++)
{
   fscanf(fp1,"%s",&c);
   if(feof(fp1))  {fclose(fp1);exit(0);}
      
sscanf(c,"%d.%d.%d.%d",&tem_ip[0], &tem_ip[1], &tem_ip[2], &tem_ip[3]);
 
  if (!(tem_ip[0] || tem_ip[1] || tem_ip[2] || tem_ip[3]))
   break;
  ptem = (IP *)malloc(sizeof(IP));
  for (i = 0; i < 4; i++)
   ptem->seg[i] = tem_ip[i];
 
  found = 0;
  pfind = pip;
  while (pfind->next != pip) {
   for (i = 0; i < 4; i++) {
    if (ptem->seg[i] < pfind->next->seg[i]) {
     found = 1;
     break;
    } else if (ptem->seg[i] > pfind->next->seg[i]) {
     break;
    }
   }
   if (found)
    break;
   pfind = pfind->next;
  }
 
  ptem->next = pfind->next;
  pfind->next = ptem;
 
 }
 
 printf("\nSorted ip address:\n");
 ptem = pip->next;
 while (ptem != pip) {
输出}；

主要是排序的那部分，输出的我懂，请各位大侠帮帮忙！


[ 本帖最后由 yangrui 于 2010-4-16 16:38 编辑 ]

我自己已经整明白了，还是谢谢你的建议