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Longest Substring Without Repeating Characters
Medium
Given a string s, find the length of the longest substring without duplicate characters.
Example 1:
Input: s = "abcabcbb" Output: 3 Explanation: The answer is "abc", with the length of 3. Note that"bca"and"cab"are also correct answers.
Example 2:
Input: s = "bbbbb" Output: 1 Explanation: The answer is "b", with the length of 1.
Example 3:
Input: s = "pwwkew" Output: 3 Explanation: The answer is "wke", with the length of 3. Notice that the answer must be a substring, "pwke" is a subsequence and not a substring.
Constraints:
0 <= s.length <= 5 * 104sconsists of English letters, digits, symbols and spaces.
Java
class Solution {
public int lengthOfLongestSubstring(String s) {
int maxLen = 0, n = s.length();
if( n == 0|| n == 1) return n;
for(int i = 0; i < n-1;i++){
int len = 1 ;
Set<Character> set = new HashSet<>();
set.add(s.charAt(i));
for(int j = i+1; j < n; j++){
if(set.contains(s.charAt(j))){
set = new HashSet<>();
break;
}
set.add(s.charAt(j));
len++;
}
maxLen = Math.max(maxLen, len);
}
return maxLen;
}
}