以下程式的目的是要找到輸入的字串中所有子字串(子字串需是輸入字串中連續字元組成) 之最大回文(Palindrome,從左往右與從右往左所得到的字元順序完全相同的字串)長度。 def longest_palindromic(s): if not s: return 0 start, max_len = 0, 1 def expand(l, r): while : l -= 1 r += 1 return (r - l - 1) for i in range(len(s)): len1 = expand(i, i) len2 = expand(i, i+1) curr_max = max(len1, len2) if curr_max > max_len: max_len = curr_max return max_len 空白處應填入什麼?
Al >= 0 and r < len(s) and s[l] == s[r]正確答案
Bl > 0 or r < len(s) and s[0] == s[r]
Cl >r or r < len(s) and s[0] == s[r]
Dl >=r and r < len(s) and s[0] == s[r
答案與詳解
