IDENTIFICATION DIVISION.
PROGRAM-ID. 172B.
ENVIRONMENT DIVISION.
INPUT-OUTPUT SECTION.
FILE-CONTROL.
  SELECT STDIO ASSIGN TO KEYBOARD. 
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DATA DIVISION.
FILE SECTION.
FD STDIO.
01 INP     PIC X(200000).
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WORKING-STORAGE SECTION.
01 S       PIC X(200001).
01 T       PIC X(200001).
01 I          PIC 9(06) COMP.
01 CNT        PIC 9(06) COMP.
01 OUT        PIC ZZZZZ9.
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PROCEDURE DIVISION.
  OPEN INPUT STDIO.
  READ STDIO.     
  MOVE INP TO S.
  READ STDIO.     
  MOVE INP TO T.
  CLOSE STDIO.
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  MOVE ZERO TO CNT.
  PERFORM VARYING I FROM 1 BY 1 UNTIL S(I:1) = ' '
    IF (S(I:1) NOT = T(I:1)) 
      ADD 1 TO CNT
    END-IF
  END-PERFORM.  
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  MOVE CNT TO OUT.
  DISPLAY FUNCTION TRIM(OUT).
  STOP RUN.
