PROBLEM DESCRIPTION
Given a string S, find the length of the longest substring with all distinct characters.
SOLUTION
This can be solved using sliding window. Maintain a HashSet to check the characters which have been visited.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
class Solution{
static int longestSubstrDistinctChars(String s){
int n = s.length();
int l = 0;
int r = 0;
Set<Character> set = new HashSet<>();
int maxLength = 0;
while(r < n){
char ch = s.charAt(r);
if(!set.contains(ch)){
maxLength = Math.max(maxLength, r-l+1);
set.add(ch);
}else{
while(set.contains(ch)){
set.remove(s.charAt(l));
l++;
}
set.add(ch);
}
r++;
}
return maxLength;
}
}