Update solution 3

Author: halfrost

leetcode/0003.Longest-Substring-Without-Repeating-Characters/3. Longest Substring Without Repeating Characters.go

@@ -31,15 +31,16 @@ func lengthOfLongestSubstring1(s string) int {
 	if len(s) == 0 {
 		return 0
 	}
-	var freq [256]int
+	var freq [127]int
 	result, left, right := 0, 0, -1
 
 	for left < len(s) {
-		if right+1 < len(s) && freq[s[right+1]-'a'] == 0 {
-			freq[s[right+1]-'a']++
+		if right+1 < len(s) && freq[s[right+1]] == 0 {
+			freq[s[right+1]]++
 			right++
+
 		} else {
-			freq[s[left]-'a']--
+			freq[s[left]]--
 			left++
 		}
 		result = max(result, right-left+1)

website/content/ChapterFour/0001~0099/0003.Longest-Substring-Without-Repeating-Characters.md

@@ -86,15 +86,16 @@ func lengthOfLongestSubstring1(s string) int {
 	if len(s) == 0 {
 		return 0
 	}
-	var freq [256]int
+	var freq [127]int
 	result, left, right := 0, 0, -1
 
 	for left < len(s) {
-		if right+1 < len(s) && freq[s[right+1]-'a'] == 0 {
-			freq[s[right+1]-'a']++
+		if right+1 < len(s) && freq[s[right+1]] == 0 {
+			freq[s[right+1]]++
 			right++
+
 		} else {
-			freq[s[left]-'a']--
+			freq[s[left]]--
 			left++
 		}
 		result = max(result, right-left+1)