题解 | #字符个数统计#

def tm010():
    while True:
        try:
            #读取字符
            s=input()
            #处理重复
            s2=''
            for i in s:
                if i in s2:
                    continue
                else:
                    s2 = s2 + i
            #输出结果
            print(len(s2))
        except:
            break
    
    

if __name__=='__main__':
    tm010()