/******************************
**          STRING.H         **
******************************/

strcmp(char *pa, char *pb) {
    while (*pa && *pb && *pa == *pb)
        ++pa, ++pb;
    return *pa - *pb;
}

strlen(char *str) {
    int pos;
    pos = str;
    while (*str++) ;
    return (str - pos - 1);
}

strcpy(char *dst, char *src) {
    int *d;
    d = dst;
    while (*d++ = *src++) ;
    return dst;
}

strncpy(char *s1, char *s2, int n) {
    int *os1;
    os1 = s1;

    while (n-- && (*s1++ = *s2++)) ;

    if (n != 0) { *s1 = 0; }

    return os1;
}

strcat(char *dst, char *src) {
    int save;
    save = dst;
    for (; *dst; ++dst);
    while (*dst++ = *src++) ;
    return (save);
}

strchr(char *str, char chr) {
    int *p;
    for(p = str; *p != 0; ++p) {
        if (*p == chr)
            return p;
    }
    return 0;
}

strrev(char *szT) {
    if (!szT)
        return "";
    int i, t, k, j, ch;
    i = strlen(szT);
    t = !(i%2)? 1 : 0;
    for(j = i - 1, k = 0; j > (i/2 - t); j--) {
        ch = szT[j];
        szT[j] = szT[k];
        szT[k++] = ch;
    }

    return szT;
}

/******************************
**           STDIO.H         **
******************************/

char *ccp = 0x7600;
int  *kbf = 0x75ff;

clrscr() {
    char *i;
    i = 0x7600;
    while (i < 0x7800) {
        *i++ = 0;
    }
}

gotoxy(int x, int y) {
    ccp = 0x7600 + (x + y * 32);
}

putc(char chr) {
    if (chr == 13) {
        ccp /= 32;
        ccp *= 32;
    } else if (chr == 10) {
        ccp += 32;
    } else {
        *ccp++ = chr | 0x0f00;
    }
}

puts(char *ptr) {
    while (*ptr) {
        putc(*ptr++);
    }
}

putd(int num) {
    int temp[5], i;
    i = 0;

    do {
        temp[i++] = num % 10 + 48;
        num /= 10;
    } while (num);


    for(--i; i != 0xffff; --i) {
        putc(temp[i]);
    }
}

putx(int xnm) {
    int temp[4], i;
    i = 3;

    do {
        int mod;
        mod = xnm % 16;
        mod += mod < 10 ? 48 : 55;
        temp[i--] = mod;
        xnm /= 16;
    } while (xnm);

    for(;i<3;) {
        putc(temp[++i]);
    }
}

printf(char *fmt) {
    int off, len;
    off = 1;
    len = strlen(fmt);

    int i;
    for(i = 0; i < len; i++) {
        if (fmt[i] == 37) {
            if (fmt[i + 1] == 100)
                { putd(*(&fmt + off++)); ++i; }
            if (fmt[i + 1] == 115)
                { puts(*(&fmt + off++)); ++i; }
            if (fmt[i + 1] == 120)
                { putx(*(&fmt + off++)); ++i; }
            continue;
        }
        if (fmt[i] == 92) {
            if (fmt[i + 1] == 110)
                { putc(13); putc(10); ++i; }
            continue;
        }
        putc(fmt[i]);
    }
}

kbhit() {
    int tmp;
    return (tmp = *kbf) ? *kbf = 0, tmp : 0;
}