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.
class Solution {
public int lengthOfLongestSubstring(String s) {
int best_so_far = 0;
HashMap<Character, Integer> map = new HashMap<>();
int start = 0;
for (int i = 0; i < s.length(); i++) {
if (map.containsKey(s.charAt(i))) {
if (map.get(s.charAt(i)) >= start) {
start = map.get(s.charAt(i)) + 1; // Because the previous character ( which was same) will not be
// considered while counting the new
// length
}
}
best_so_far = Math.max(best_so_far, i - start + 1);
map.put(s.charAt(i), i);
}
return best_so_far;
}
}