磁盘读写

有两个磁盘文件，各存放一行字母，今要求把这两个文件中的信息合并（按字母顺序排列），输出到一个新的文件中去。

 

#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[n], fp);
    }
    return 0;
}