磁盘读写

#include <stdio.h>
#include <stdlib.h>

int main()
{
FILE* fp;
//文件1
if ((fp = fopen("E:\\test\\text\\text1.txt","r")) == NULL)
{
printf("can not open file\n");
exit(0);
}
char ch;
char a[100];
int i;
for (i = 0; (ch = fgetc(fp)) != EOF; i++)
{
a[i] = ch;
}
//文件2
if ((fp = fopen("E:\\test\\text\\text2.txt", "r")) == NULL)
{
printf("can not open file\n");
exit(0);
}
for (; (ch = fgetc(fp)) != EOF; i++)
{
a[i] = ch;
}

//排序
char temp;
for (int j = 0; j < i; j++)
{
for (int k = j+1; k < i; k++)
{
if (a[k]<a[j])
{
temp = a[j];
a[j] = a[k];
a[k] = temp;
}
}
}
//写入文件3
if ((fp = fopen("E:\\test\\text\\text3.txt", "w")) == NULL)
{
printf("can not open file\n");
exit(0);
}
for (int n=0;n<i; n++)
{
putc(a
, fp);
}
return 0;
}