程序代码：

#include <stdio.h>

main()
{
    FILE *fp = fopen("test.txt", "r");
    if (fp == NULL)
    {
        return 0;
    }
    char s[256];
    char *p1, *p2;
    while (fgets(s, 256, fp) != NULL)
    {
        p1 = s;
        while (*p1++ != ' ') NULL;
        p2 = p1;
        while (*p2++ != ' ') NULL;
        *--p2 = '\0';
        printf("%s\n", p1);
    }
    fclose(fp);
}