3. 无重复字符的最长子串
3. Longest Substring Without Repeating Characters
题目描述
Given a string, find the length of the longest substring without repeating characters.
给定一个字符串，请你找出其中不含有重复字符的 最长子串 的长度。
LeetCode3. Longest Substring Without Repeating Characters中等
Example 1:
Input: "abcabcbb"
Output: 3
Explanation: The answer is "abc", with the length of 3.
Example 2:
Input: "bbbbb"
Output: 1
Explanation: The answer is "b", with the length of 1.
Example 3:
Input: "pwwkew"
Output: 3
Explanation: The answer is "wke", with the length of 3.
Note that the answer must be a substring, "pwke" is a subsequence and not a substring.
Java 实现
import java.util.HashSet;
import java.util.Set;
class Solution {
public int lengthOfLongestSubstring(String s) {
int i = 0, j = 0, max = 0;
Set<Character> set = new HashSet<>();
while (j < s.length()) {
if (!set.contains(s.charAt(j))) {
set.add(s.charAt(j++));
max = Math.max(max, set.size());
} else {
set.remove(s.charAt(i++));
}
}
return max;
}
}
相似题目
参考资料
- https://leetcode.com/problems/longest-substring-without-repeating-characters/
- https://leetcode-cn.com/problems/longest-substring-without-repeating-characters/