#include<stdio.h>

#include<stdlib.h>

#include<string.h>

void main()

{

FILE *fpa,*fpb,*fpc;

char k[300]={0},kk[300]={0}; //k是b裡的字串,kk是a裡的字串

fpa=fopen("a.txt","r");

fpb=fopen("b.txt","r");

fpc=fopen("c.txt","w"); //先把內容存在檔案c裡，再轉到a裡面

if(fpa==NULL||fpb==NULL)

{

printf("開啟檔案失敗\n");

printf("請確認你是否已新建好\"a.txt\"和\"b.txt\"\n");

return;

}

fscanf(fpb,"%s",k);

fscanf(fpa,"%s",kk);

{

if(strcmp(kk,k)!=0) /* 無相同內容 */

{

fprintf(fpc,"%s\n",kk);

}

memset(kk,0,sizeof(kk));

fscanf(fpa,"%s",kk);

}

fclose(fpa);

fclose(fpb);

fclose(fpc);

fpc=fopen("c.txt","r");

fpa=fopen("a.txt","w");

memset(kk,0,sizeof(kk));

fscanf(fpc,"%s",kk);

while(kk[0]!="\0") //開始轉到a裡面

{

fprintf(fpa,"%s\n",kk);

memset(kk,0,sizeof(kk));

fscanf(fpc,"%s",kk);

}

fclose(fpc);

system("del c.txt"); //把新建的c.txt刪掉

printf("已完成\n");

}