a=list(input()) D=dict() for i in a: if i in D: D[i]+=1 else: D[i]=1 L=[] for i in D.items(): L.append([i[0],i[1]]) L.sort(key=lambda t: t[1]) ans=0 if len(L)>2: for i in L[:-2]: ans+=i[1] print(ans)