680. Valid Palindrome II
Given a non-empty string s
, you may delete at most one character. Judge whether you can make it a palindrome.
Example 1:
代码语言:javascript复制Input: "aba"
Output: True
Example 2:
代码语言:javascript复制Input: "abca"
Output: True
Explanation: You could delete the character 'c'.
Note:
- The string will only contain lowercase characters a-z. The maximum length of the string is 50000.
思路:
题目是让判断一个非空字符串在可以删除一个字符的情况下,是否是回文字符串。从贪心的角度考虑,可以发现如果一个字符串符合这种情况,一定是对于一个源串,去掉首或者尾的字符之后,剩下的字符串是回文的,因为字符串非空且只会为a-z,所以相比125题,不需要再去检验字符。
代码:
go:
代码语言:javascript复制func validPalindrome(s string) bool {
i, j := 0, len(s) - 1
for i < j {
if s[i] != s[j] {
return isValidPalindrome(s, i 1, j) || isValidPalindrome(s, i, j-1)
}
i
j--
}
return true
}
func isValidPalindrome(s string, i, j int) bool {
for i < j {
if s[i] != s[j] {
return false
}
i
j--
}
return true
}