---

.model small
.stack 100h
.data
    a db -50
    b db 30
    f dw ?
.code
start:
    mov ax, @data
    mov ds, ax

    mov al, a
    cbw
    mov bl, 19
    idiv bl
    cmp ah, 0
    jge ok1
    add ah, 19
ok1:
    mov bh, 0
    mov bl, ah

    mov al, b
    cbw
    mov cl, 17
    idiv cl
    cmp ah, 0
    jge ok2
    add ah, 17
ok2:
    mov ch, 0
    mov cl, ah

    add bx, cx
    mov f, bx

    mov ax, 4c00h
    int 21h
end start