Longest Substring Without Repeating Characters

Title Description

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

Example 1:

Input: s = "abcabcbb"
Output: 3
Explanation: The answer is "abc", with the length of 3.

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.

Topic analysis

No repeat longest string , The dictionary can be used to judge whether there are duplicate values , From the first , Move to the right first , Until a duplicate character appears , Now move the left , Until repeated characters are excluded , Continue to move the right , Record every time result Value , Retain the maximum value .

func lengthOfLongestSubstring(s string) int {
    
	if len(s) == 0 {
    
		return 0
	}
	var bitSet [256]bool
	result, left, right := 0, 0, 0
	for left < len(s) {
    
		if bitSet[s[right]] {
    
			bitSet[s[left]] = false
			left++
		} else {
    
			bitSet[s[right]] = true
			right++
		}
		if result < right-left {
    
			result = right - left
		}
		if left+result >= len(s) || right >= len(s) {
    
			break
		}
	}
	return result
}
func main() {
    
	s := "aabbccddabcde"

	fmt.Println(lengthOfLongestSubstring(s))
}