num=input()
num=list(map(int,num))
num.reverse()
num_c=[]
for i in num:
    if i not in num_c:
        num_c.append(i)
num_c.reverse()
j=1
num_f=0
for i in num_c:
    num_f=num_f+i*j
    j=j*10
print(num_f)