Longest Substring Without Repeating Characters

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Just have an array to keep track of all the previous letters we hit. After we reach a previously hit letter, simply start over with a new position.

public class Solution {
    public int lengthOfLongestSubstring(String s) {
        
        int result = 0;
        boolean[] hit = new boolean[256];
        
        char[] c = s.toCharArray();
        
        int incre = 0;
        for(int i=0; i< c.length; i++){
            for(int j=i; j< c.length; j++){
                if(hit[c[j]]){
                    result = Math.max(result, incre);
                    incre = 0;
                    Arrays.fill(hit,false);
                    break;
                }
                else{
                    hit[c[j]]=true;
                    incre++;
                }
            }
        }
        result = Math.max(result, incre);
        return result;
    }
}