New

.MODEL SMALL
.STACK 100

.DATA

    NUM1 DB ?
    NUM2 DB ?
    NUM3 DB ?
    NUM4 DB ?
    RESULT DB ?
    MSG1 DB "ENTER 1ST NUMBER : $"
    MSG2 DB 10,13, "ENTER 2ND NUMBER : $"
    MSG3 DB 10,13, "ENTER 3RD NUMBER : $"
    MSG4 DB 10,13, "ENTER 3RD NUMBER : $"
    MSG DB 10,13, "OUTPUT : $"

.CODE

MAIN PROC

    MOV AX, @DATA
    MOV DS, AX

    LEA DX, MSG1
    MOV AH, 9
    INT 21H

    MOV AH, 1
    INT 21H
    SUB AL, 30H
    MOV NUM1, AL

    LEA DX, MSG2
    MOV AH, 9
    INT 21H

    MOV AH, 1
    INT 21H
    SUB AL, 30H
    MOV NUM2, AL

    ADD AL, NUM1
    ADD AL, 30H

    MOV BL, AL
    SUB BL, 30H

    LEA DX, MSG3
    MOV AH, 9
    INT 21H

    MOV AH, 1
    INT 21H

    MOV CL, AL
    SUB CL, 30H

    SUB BL, CL

    ADD BL, 30H

    SUB BL, 30H

    LEA DX, MSG4
    MOV AH, 9
    INT 21H

    MOV AH, 1
    INT 21H

    SUB AL, 30H

    ADD AL, BL
    ADD AL, 30H

    MOV DL, AL
    MOV AH, 2
    INT 21H

    MOV AH, 4CH
    INT 21H

MAIN ENDP
END MAIN