比较两个字符串，取其中最大的重复字符串006

// 选出两个字符串中首个最大的重复字符串
    public String MaxRepeatStr(String str1,String str2){
        
        String longStr = "";
        String shortStr = "";
        if(str1.length() <= str2.length()){
            shortStr = str1;
            longStr = str2;
        } else{
            shortStr = str2;
            longStr = str1;
        }
        
        int i = shortStr.length();
        int j = 0;
        while(i>0){
            for(int k = 0;k<=j;k++){
                if (longStr.indexOf(shortStr.substring(k, i+k)) >= 0){
                    System.out.println("Has max String is " + shortStr.substring(k, i+k));
                    return shortStr.substring(k, i+k);
                }
            }
            
            i--;
            j++;
        }
        System.out.println("Didn't Has max String.");
        return "";
    }

//优化版
// 选出两个字符串中最大的重复字符串以及出现的次数
    public Map MaxAllRepeatStr(String str1,String str2){
        
        Map<String,Integer> map = new HashMap<>();
        
        String longStr = "";
        String shortStr = "";
        if(str1.length() <= str2.length()){
            shortStr = str1;
            longStr = str2;
        } else{
            shortStr = str2;
            longStr = str1;
        }
        
        int i = shortStr.length();
        int j = 0;
        boolean hasflag = false;
        while(i>0){
            for(int k = 0;k<=j;k++){
                //在for循环里，i是不变的，是本次循环中取得字符串长度
                // i+k == endIndex
                if (longStr.indexOf(shortStr.substring(k, i+k)) >= 0){
                    if(map.get(shortStr.substring(k, i+k)) != null){
                        map.put(shortStr.substring(k, i+k), map.get(shortStr.substring(k, i+k)) + 1);
                    } else{
                        map.put(shortStr.substring(k, i+k), 1);
                    }
                    hasflag = true;
                }
            }
            if(hasflag){
                return map;
            }
            
            i--;
            j++;
        }
        System.out.println("Didn't Has max String.");
        return map;
    }