题解 | #字符个数统计#
字符个数统计
https://www.nowcoder.com/practice/eb94f6a5b2ba49c6ac72d40b5ce95f50
哈希表
while True:
try:
s = input()
dp = dict()
for i in s:
if i not in dp:
dp[i] = 1
print(len(dp))
except:
break