INCLUDE IO.ASM

STK SEGMENT
    DW 128 DUP(?)
STK ENDS

DATA SEGMENT
    A DW ?
    B DW ?

    TWO DW 2

    ERR_1 DB 'ONE NUMBER ARE NEGATIVE!', '$'
    ERR_2 DB 'BOT NUMBERS ARE ODD!', '$'
DATA ENDS

CODE SEGMENT
    ASSUME SS: STK, DS: DATA, CS: CODE

    main PROC
        PUSH DS             ; SAVE DS

        MOV AX, DATA        ; INIT DS
        MOV DS, AX          ;

        MOV AX, 0000h       ; TELL OS, WHERE MY STACK STARTS
        PUSH AX             ;

        inint A             ; READ VARIABLES
        inint B             ;

        MOV AX, A
        CMP AX, 0
        JL bad_1            ; IF A < 0 PRINT THIS

        MOV AX, B
        CMP AX, 0
        JL bad_1            ; IF A AND B < 0 SKIP *2 GO TO COND2

        MOV AX, A           ; MULTIPLY BY 2 AND PRINT
        MUL TWO             ;
        outch 2Bh           ;
        outch 20h           ;
        outint AX           ;

        newline

        MOV AX, B           ; MULTIPLY BY 2 AND PRINT
        MUL TWO             ;
        outch 2Bh           ;
        outch 20h           ;
        outint AX           ;

        JMP cnd2            ; IF OKAY => SKIP ERROR

bad_1:  MOV AH, 09h         ; IF ONE NUMBER - NEGATIVE => PRINT ERROR
        LEA DX, ERR_1
        INT 21h

cnd2:   MOV AX, A           ; IS (A % 2) == 0?
        IDIV TWO            ; IF A EVEN => A-=2, B-=2
        CMP DX, 0           ;
        JE good2            ;

        MOV AX, B
        IDIV TWO
        CMP DX, 0
        JE good2

        MOV AH, 09h         ; IF BOTH NUMBERS ARE ODD => PRINT ERROR
        LEA DX, ERR_2
        INT 21h

        JMP fin             ; IF BOTH CONDITIONS - FALSE => FINISH PROGRAM

good2:  newline
        MOV AX, A           ; SUB 2 AND PRINT
        SUB AX, 2           ;
        outch 2Dh           ;
        outch 20h           ;
        outint AX           ;

        newline

        MOV AX, B           ; SUB 2 AND PRINT
        SUB AX, 2           ;
        outch 2Dh           ;
        outch 20h           ;
        outint AX           ;

fin:    MOV AH, 4Ch         ; END PROGRAM
        INT 21h
    main ENDP
CODE ENDS

    END main