//My code can run most test cases correctly, except those with "" (e.g. ""\qwertq"").

//I am really confused about it, could you help me? Thanks!

```
public class Solution {
public int lengthOfLongestSubstring(String s) {
if(s.length() == 0)
return s.length();
int max = 1;
for(int i = 0; (i+1)<s.length(); i++){
int j = i+1;
int count = 1;
while(j < s.length() && !s.substring(i,i+1).equals(s.substring(j,j+1)) ){
boolean dup = false;
int tempI = i+1;
while(tempI < j){
if(s.substring(tempI, tempI+1).equals(s.substring(j,j+1))){
dup = true;
break;
}
tempI ++;
}
if(dup == true)
break;
count ++;
j ++;
}
if(count > max)
max = count;
}
return max;
}
}
```