for_zheka

STEG SEGMENT PARA STACK "STACK"
DB 64 DUP("STACK")
STEG ENDS



DSEG SEGMENT PARA PUBLIC "DATA"

HELLO_STRING DB 'Enter your number from -333 to 333: ',13,10,'$'
OUTPUT_STRING DB 13,10,"Your number: ",'$'
ERROR_STRING DB 13,10,'Error! Incorrect input!',13,10,'$'
INPUT DB 5,?,5 DUP('$')
IS_NEGATIVE DB 1 DUP('0')

DSEG ENDS



CSEG SEGMENT PARA PUBLIC "CODE"

MAIN PROC FAR
assume SS:STEG, DS:DSEG, CS:CSEG

PUSH DS
PUSH AX
XOR AX, AX; MOV AX,0
MOV AX, DSEG
MOV DS, AX

CALL INPUT_NUMBER
CALL OUTPUT_NUMBER

mov ah, 08h;ah - elder bite of AX. 8(read 1 symbol)2(outout 1 symb)9(str on screen)10(read str to enter)
    int 21h

mov ax,4C00h;dos func exit from program
    int 21h

MAIN ENDP




INPUT_NUMBER PROC NEAR;near 128 byte stack

MOV AH, 9;output str
LEA DX, HELLO_STRING
INT 21H

LEA DX, INPUT
MOV AH, 10;read line
INT 21H

LEA DI, INPUT+2
MOV AL, [DI]
CMP AL, '-';zf 1
JE NEGATIVE;if zf==1
CMP AL,'+'
JE POSITIVE

LABEL1:
   XOR BX,BX;bx==0
   MOV BX,10
   XOR AX,AX

LABEL2:
   XOR CX,CX                 ; ERROR SYMBOL
   CMP BYTE PTR [DI], 0DH;compare 3rd+ byte==$
   JZ LABEL5;if zf==1 ->
   CMP BYTE PTR [DI], 30H;<0
   JB ERROR;if cf==1 ->
   CMP BYTE PTR [DI], 39H;>9
   JA ERROR;if cd,zf==0,0
   MOV CL, [DI]
   SUB CL, 30H;cl=cl-30h translate to hex
   MUL BX ;AX=BX*AX MUL (BX==10)
   JC ERROR;(65512)if cf==0 ->
   ADD AX,CX;AX+CX
   JC ERROR
   INC DI;DI++
   JMP LABEL2;if CX!=0 then ->

NEGATIVE:
   PUSH AX;put in stack
   MOV AL, 1
   MOV IS_NEGATIVE, AL
   POP AX;get from stack
   INC DI
   JMP LABEL1

POSITIVE:
   PUSH AX
   MOV AL, 0
   MOV IS_NEGATIVE, AL
   POP AX
   INC DI
   JMP LABEL1

ERROR:
   MOV AH, 9
   LEA DX, ERROR_STRING
   INT 21H

   mov  ah, 08h
    int 21h

   mov ax,4C00h
    int 21h

LABEL5:
   CMP AX, 333;zf,cf = 0,0
   JA ERROR
   MOV CL, IS_NEGATIVE
   CMP CL, 1;if cl==1 then zf=1
   JNZ L6; if zf!=0 call ->
   NEG AX;*(-1)

L6:   RET;return
INPUT_NUMBER ENDP



OUTPUT_NUMBER PROC NEAR


MOV CX, AX;for jumper

MOV AH, 9
LEA DX, OUTPUT_STRING
INT 21H

MOV AX,CX
MOV BL, IS_NEGATIVE
CMP BL, 1
JNZ POS;zf!=0->

MOV AH,2;interrupt 1 symbol
MOV DL, '-'
INT 21H

MOV AX,CX
NEG AX
POS:
   XOR CX,CX ;CX = 0
   XOR BX,BX
   MOV BX,10 ;BL=10
L1:
   XOR DX,DX
   DIV BX           ; AX /(DIVIDE) BX RESULT DX
   PUSH DX
   INC CX

   TEST AX,AX       ; IF AX = 0, ZF = 1
   JNZ L1
   MOV AH,2
L2:
   POP DX
   ADD DL, 30H;translate to dec
   INT 21H
   LOOP L2;while cx !=0->

RET

OUTPUT_NUMBER ENDP

CSEG ENDS
END MAIN