Q
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.
Example 4:
Input: s = ""
Output: 0
A
class Solution {
public:
int lengthOfLongestSubstring(string s) {
int n = s.length();
int res = 0;
for (int i = 0; i < n; i++) {
for (int j = i; j < n; j++) {
if (checkRepetition(s, i, j)) {
res = max(res, j - i + 1);
}
}
}
return res;
}
bool checkRepetition(string& s, int start, int end) {
vector<int> chars(128);
for (int i = start; i <= end; i++) {
char c = s[i];
chars[c]++;
if (chars[c] > 1) {
return false;
}
}
return true;
}
};