...输入一行字符,分别统计出其英文字母和数字字符的个数答:s=input("请输入一行字符:\n")alpha,num,space,other=0,0,0,0 for i in s:if i.isalpha():alpha+=1 elif i.isdigit():num+=1 elif i.isspace():space+=1 else:other+=1 print('英文字符数{},数字字符数{},空格字符数{},其他字符数{}'.format(alpha,num,space,other))...