10 INPUT A$:S=0
20 FOR I=1 TO LEN(A$) 
30    P=0
40    FOR J=1 TO LEN(A$)
50       IF MID$(A$,I,1)=MID$(A$,J,1) THEN P=P+1
60    NEXT J
70    IF P>1 THEN S=S+1/P
80 NEXT I
90 PRINT FIX(S+.5):END