STACK SEGMENT STACK
    DB 200 DUP (0)
STACK ENDS
DATA SEGMENT
  INPUT DB "PLEASE INPUT (0...9): $"
DATA ENDS
CODE SEGMENT 
       ASSUME CS: CODE, DS: DATA, SS: STACK
BEGIN: MOV AX, DATA
       MOV DS, AX
       SUB AX, AX
       MOV AH, 9
       LEA DX, INPUT
       INT 21H
       MOV AH, 1
       INT 21H
       MUL AL
       MUL AX
       MOV AH, 4CH
       INT 21H
CODE ENDS
END BEGIN