bits 16
org 0x7c00

start:
    ;
    xor ax, ax
    mov ds, ax
    mov es, ax
    mov si, 0xb800
    mov di, si
    mov cx, 80*25
    cld
    rep stosw
    
    ; 
    mov si, msg
    mov ah, 0x0e
    mov bh, 0
print:
    lodsb
    cmp al, 0
    je input
    int 0x10
    jmp print
    
    ; 
input:
    xor ax, ax
    int 0x16
    mov bl, al
    
    ; 
    cmp bl, 0x37
    jne wrong
    mov si, msg2
    mov ah, 0x0e
    mov bh, 0
print2:
    lodsb
    cmp al, 0
    je start
    int 0x10
    jmp print2
    
    ;
wrong:
    mov si, msg3
    mov ah, 0x0e
    mov bh, 0
print3:
    lodsb
    cmp al, 0
    je start
    int 0x10
    jmp print3
    
msg db "guess an number（0-9）：", 0
msg2 db "congratulations，you are right！", 0
msg3 db "sorry，you can try again！", 0

times 510-($-$$) db 0
dw 0xaa55