temp = input()
data = []
ace = []
for i in temp:
if i in data:
ace[data.index(i)] += 1
else:
data.append(i)
ace.append(1)
p = min(ace)
for i in temp:
if ace[data.index(i)] != p:
print(i,end="")
else:
continue输入：aabcddd
输出：aaddd
