''' 【程序17】 题目:输入一行字符,分别统计出其中英文字母、空格、数字和其它字符的个数。 1.程序分析:利用while语句,条件为输入的字符不为'\n'.        2.程序源代码: ''' import string s = raw_input('input a string:\n') letters = 0 space = 0 digit = 0 others = 0 for c in s: if c.isalpha(): letters += 1 elif c.isspace(): space += 1 elif c.isdigit(): digit += 1 else: others += 1 print 'char = %d,space = %d,digit = %d,others = %d' % (letters,space,digit,others)