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Given a string s, find the length of the longest substring without repeating characters.
Test Cases
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.
Solution
class Solution {
public:
int lengthOfLongestSubstring(string s) {
int n = s.length();
int maxLength = 0;
vector<int> charIndex(128, -1);
int left = 0;
for (int right = 0; right < n; right++) {
if (charIndex[s[right]] >= left) {
left = charIndex[s[right]] + 1;
}
charIndex[s[right]] = right;
maxLength = max(maxLength, right - left + 1);
}
return maxLength;
}
};class Solution {
public int lengthOfLongestSubstring(String s) {
Map<Character, Integer> map = new HashMap<>();
int start = 0, max = 0;
for(int i=0; i<s.length(); i++) {
if (map.containsKey(s.charAt(i))) {
start = Math.max(start, map.get(s.charAt(i))+1);
}
max = Math.max(max, i-start+1);
map.put(s.charAt(i), i);
}
return max;
}
}class Solution:
def lengthOfLongestSubstring(self, s: str) -> int:
mp, start, mxl = {}, 0, 0
for i in range(len(s)):
if s[i] in mp:
start = max(start, mp[s[i]] + 1)
mxl = max(mxl, i - start + 1)
mp[s[i]] = i
return mxlfunction lengthOfLongestSubstring(s: string): number {
const map = new Map<string, number>();
let index = 0, start = 0, maxlength = 0;
while(index < s.length) {
if (map.has(s[index])) {
start = Math.max(start, map.get(s[index])+1);
}
maxlength = Math.max(maxlength, index-start+1);
map.set(s[index], index);
index++;
}
return maxlength;
};