05 No-repeat Substring (hard) √

Problem Statement#

Given a string, find the length of the longest substring, which has all distinct characters.

Example 1:

Input: String="aabccbb"Output: 3Explanation: The longest substring with distinct characters is "abc".

Example 2:

Input: String="abbbb"Output: 2Explanation: The longest substring with distinct characters is "ab".

Example 3:

Input: String="abccde"Output: 3Explanation: Longest substrings with distinct characters are "abc" & "cde".

不重复的连续子字符串

  public static int findLength(String str) {
        HashMap<Character, Integer> map = new HashMap<>();
        int sum = 0;
        char[] chars = str.toCharArray();
        int start = 0;
        int result = Integer.MIN_VALUE;
        for(int i = 0; i < chars.length; i++){
            char c = chars[i];
            map.put(chars[i],map.getOrDefault(c,0) + 1);
            while ( map.getOrDefault(c, 0) > 1){
                map.put(chars[start],map.getOrDefault(chars[start], 0) -1);
                start++;
            }
            result = Math.max(result, i - start + 1);

        }
        return result != Integer.MIN_VALUE ? result : -1;
  }