滑动窗口解决最长递增子序列问题

      给定一个只包含数字的字符串，例如“127343456”，找出最长递增子序列，例如上面的就是3456就是最长递增子序列.

       可以使用滑动窗口来解决这个问题，从而在O(n)的时间复杂度内完成.

public static Pair<Integer, Integer> getMaxIncreSubStr(String s){
        int maxLength = 0;
        int startResult = 0;


        int start = 0;
        int end = start + 1;
        int length = s.length();
        while(start < length && end < length){
            int current = s.charAt(end);
            int before = s.charAt(end - 1);
            if(current == before + 1){
                if(end == length - 1){
                    int tempLength = end - start + 1;
                    if(tempLength > maxLength){
                        maxLength = tempLength;
                        startResult = start;
                    }
                }
                end++;
            }else{
                int tempLength = end - start;
                if(tempLength > maxLength){
                    maxLength = tempLength;
                    startResult = start;
                }
                start = end;
                end = start + 1;
            }
        }

        return new Pair<>(maxLength, startResult);
    }