在制定内存查找指定字符，显示该字符相对于起始地址的偏移量(找到几个显示几个)

否则返回－1 （本程序利用si作为标志位，初始值为-1；找到了则大于-1；没找到则仍为-1）

寄存器：ax,bx,cx,dx,bp,si-Find the specified character in the development of memory, showing the character relative to the starting address offset (to find a few shows a few)　otherwise it returns-1 (si use of this procedure as a flag, the initial value of-1　to find the is greater than-1　not find the remains-1)　registers: ax, bx, cx, dx, bp, si