LNDS

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package 无重复字符的最长字符串;

import java.util.HashSet;
import java.util.Set;

/**
 *
 * @author junye.mao
 */
public class LNDS {

    /**
     * @param args the command line arguments
     */
    public static int LengthOfLongestSubString(String s){
    int length = s.length();
    int result = 0, StartInd = 0, EndInd = 0;
    Set<Character> substring = new HashSet<>();
    while(StartInd < length && EndInd < length){
    if(!substring.contains(s.charAt(EndInd))){
    substring.add(s.charAt(EndInd++));
    result = Math.max(result, EndInd - StartInd);
    }else{
    substring.remove(s.charAt(StartInd++));
    } 
    }
    return result;
    }
    public int LengthOfLongestSubString2(String s){
    int length = s.length();
    int result=0 ;
    for(int n = 0; n<length; n++){
     for(int m = n+1; m<=length; m++){
     if(judge(s,n,m))
         result = Math.max(result,m-n);
    }
    }
    return result;
    }
    public  boolean judge(String s, int startInd , int endInd){
    Set<Character> set = new HashSet<>();
        for(int i = startInd; i<endInd; i++){
        if(set.contains(s.charAt(startInd))) return false;
        set.add(s.charAt(startInd));
        }
        return true;
    }
    
    public static void main(String[] args) {
        String a = "aabbddhhsdfe";
        int b = LNDS.LengthOfLongestSubString(a);
        System.out.println(b);
        
 // TODO code application logic here
    }
    
}