倒三角.asm

用汇编编写的

        DATA  SEGMENT
          A1  DB        0AH,0DH,'$'
          A2  DB        0AH,0DH,'Input the number:','$'
        DATA  ENDS

      STACK1  SEGMENT   PARA   STACK
              DW        20H    DUP(0)
      STACK1  ENDS

        CODE  SEGMENT
              ASSUME    CS:CODE, DS:DATA, SS:STACK1
      START:  MOV       AX,DATA
              MOV       DS,AX
              LEA       DX, A2
              MOV       AH, 9
              INT       21H
              MOV       AH,1
              INT       21H
              SUB       AL, 30H
              TEST      AL, 01H
              JNE       PASS
              INC       AL
       PASS:  MOV       BL, AL
              MOV       BH, 0

       OUT1:  LEA       DX,A1
              MOV       AH,9
              INT       21H
              MOV       CL, BL
              MOV       CH, 0
              MOV       DH, BH

              CMP       DH, 0
              JE        O2

         O1:  MOV       DL, ' '
              MOV       AH, 2
              INT       21H
              DEC       DH
              CMP       DH, 0
              JG        O1

         O2:  MOV       DL, '*'
              MOV       AH, 2
              INT       21H
              LOOP      O2

              INC       BH
              DEC       BL
              DEC       BL
              CMP       BL, 0
              JG        OUT1

              LEA       DX,A1
              MOV       AH,9
              INT       21H
              MOV       AX,4C00H
              INT       21H
        CODE  ENDS
              END       START