Topcoder過去問
http://sns.atfb.jp/view_diary/43/28802.html
def count(a, b): """ >>> count(1, 5) 1 >>> count(6, 10) 1 >>> count(1, 10) 2 >>> count(1, 20) 4 >>> count(140, 150) 10 >>> count(170, 180) 10 """ count = 0 for i in range(a, b): if( str(i).find('4') != -1 or str(i).find('7') != -1 ): count += 1 return count if __name__ == '__main__': import doctest doctest.testmod()