.MODEL SMALL
.STACK 100
PRINT MACRO MSG
      MOV AH,09
      LEA DX,MSG
      INT 21H
      ENDM
.DATA
MSG1 DB 0DH,0AH, 'ENTER A STRING:$'
SRC  DB 80
     DB ?
     DB 30 DUP(?)
MSG2 DB 0DH,0AH,'ENTER A CHARACTER:$'
MSG3 DB 0DH,0AH,'THE CHARACTER IS FOUND$'
MSG4 DB 0DH,0AH,'THE CHARACTER IS NOT FOUND$'
.CODE
START: MOV AX,@DATA
       MOV DS,AX
       MOV ES,AX
       PRINT MSG1
       LEA DX,SRC
       MOV AH,0AH
       INT 21H
       PRINT MSG2
       MOV AH,01H
       INT 21H
       MOV CL,SRC+1
       MOV CH,00
       LEA DI,SRC
       ADD DI,0002
       CLD
REPNE SCASB
      JE FOUND
      PRINT MSG4
      JMP EXIT
FOUND: PRINT MSG3
EXIT: MOV AH,4CH
              INT 21H
              END START