(2A - 3B)/5C

section .data
  msg_zero_div db "ERROR: Zero division!", 10
  len_zero_div equ $ - msg_zero_div
  msg_negative db "Negative numerator", 10
  len_negative equ $ - msg_negative
  msg_zero db "0", 10
  len_zero equ $ - msg_zero
  msg_cat db "quo="
  len_cat equ $ - msg_cat
  msg_rest db 10, "rem="
  len_rest equ $ - msg_rest
  newline db 10

section .bss
  a resb 2
  b resb 2
  c resb 2
  quo resb 2
  rem resb 2

section .text
global _start

_start:
  ; read A
  mov eax, 3
  mov ebx, 0
  mov ecx, a
  mov edx, 2
  int 0x80

  ; read B
  mov eax, 3
  mov ebx, 0
  mov ecx, b
  mov edx, 2
  int 0x80

  ; read C
  mov eax, 3
  mov ebx, 0
  mov ecx, c
  mov edx, 2
  int 0x80

  ; compute
  movzx eax, byte [a]
  sub eax, '0'
  mov ebx, 2
  mul ebx       ; 2A

  mov ebx, eax

  movzx eax, byte [b]
  sub eax, '0'
  mov ecx, 3
  mul ecx         ; 3B

  sub ebx, eax

  ; if quo is 0
  cmp ebx, 0
  je zero_result

  ; if quo < 0
  cmp ebx, 0
  jl negative_result

  movzx ecx, byte [c]
  sub ecx, '0'
  mov eax, 5
  mul ecx         ; 5C

  ; if zero div
  cmp eax, 0
  je zero_division

  mov ecx, eax
  mov eax, ebx
  cdq
  div ecx

  ; print quo
  add eax, '0'
  mov [quo], al

  mov eax, 4
  mov ebx, 1
  mov ecx, msg_cat
  mov edx, len_cat
  int 0x80

  mov eax, 4
  mov ebx, 1
  mov ecx, quo
  mov edx, 1
  int 0x80

  ; print quo
  mov eax, edx
  add eax, '0'
  mov [rem], al

  mov eax, 4
  mov ebx, 1
  mov ecx, msg_rest
  mov edx, len_rest
  int 0x80

  mov eax, 4
  mov ebx, 1
  mov ecx, rem
  mov edx, 1
  int 0x80

  mov eax, 4
  mov ebx, 1
  mov ecx, newline
  mov edx, 1
  int 0x80

  jmp exit

zero_division:
  mov eax, 4
  mov ebx, 1
  mov ecx, msg_zero_div
  mov edx, len_zero_div
  int 0x80
  jmp exit

negative_result:
  mov eax, 4
  mov ebx, 1
  mov ecx, msg_negative
  mov edx, len_negative
  int 0x80
  jmp exit

zero_result:
  mov eax, 4
  mov ebx, 1
  mov ecx, msg_zero
  mov edx, len_zero
  int 0x80
  jmp exit

exit:
  mov eax, 1
  xor ebx, ebx
  int 0x80