#include <stdio.h>
#include <string.h>
#define   N   1000
int main(void)
{
    char ch, str[N];
    int i = 0;
    while(1)
    {
        ch = getchar();
        while(ch != EOF)
        {
            str[i] = ch;
            i ++;
            if(ch == '\n')
                break;
            ch = getchar();
        }
        if(ch == EOF)
            break;
        else if(str[5] == '-')
            printf("I am showing help.\n");
        else if(str[5] == 'e'||str[5] == 'o')
            printf("I am a c89 preprocessor + compiler + linker. I start from \"hello.c\" and end with \"a.exe\".\n");
        else if(str[5] == 'c')
            printf("I am a c89 preprocessor + compiler. I start from \"hello.c\" and end with \"hello.o\".\n");
        else if(str[5] == 'E')
            printf("I am a c89 preprocessor. I start from \"hello.c\" and end with \"expanded.c\".\n");
        else
        {
            if(str[14] == 'e')
                printf("I am a c99 preprocessor + compiler + linker. I start from \"hello.c\" and end with \"a.exe\".\n");
            else if(str[14] == 'c')
                printf("I am a c99 preprocessor + compiler. I start from \"hello.c\" and end with \"hello.o\".\n");
            else if(str[14] == 'o')
                printf("I am a c99 preprocessor. I start from \"hello.c\" and end with \"foobar.c\".\n");
        }
        i = 0;
    }
return 0;
}
这是我写的一段代码!我知道有很多错误!

该学习了。。。

 
											





 
	    