class Solution {
    public int lengthOfLongestSubstring(String s) {
        if(s.length()==0)
        {
           return 0;
        }
        int max=Integer.MIN_VALUE;
        for(int i=0;i<s.length();i++){
            for(int j=i+1;j<=s.length();j++){
                String req=s.substring(i,j);//i to j-1
                boolean found = checkforduplicates(req);
                 if(found==true){
                    if(req.length()>max)
                    {
                        max=req.length();
                    }
                 }
            }
        }
        return max;
    }
    boolean checkforduplicates(String str){
          String req="";
          for(int i=0;i<str.length();i++){
                if(!req.contains(str.charAt(i)+"")){
                    req=req+str.charAt(i)+"";
                }else{
                    return false;
                }
          }
          return true;
    }
}
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