leetcode-3

Given a string, find the length of the longest substring without repeating characters.

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.

来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/longest-substring-without-repeating-characters
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My solution:

class Solution {
    public int lengthOfLongestSubstring(String s) {
        int len = s.length(), result = 0;
        Map<Character, Integer> charIdxMap = new HashMap<>();
        for(int start = 0, end = 0; end < len; end++){
            char curChar = s.charAt(end);
            if(charIdxMap.containsKey(curChar)){
                start = Math.max(charIdxMap.get(curChar), start);
            }
            result = Math.max(result, end - start + 1);
            charIdxMap.put(curChar, end + 1);
        }
        return result;
    }
}