掘金.找出最长的神奇数列（简单09）

public class Main {
    public static String solution(String inp) {

        StringBuffer sb = new StringBuffer();
        int sb_len = 1;
        for (int i = 0; i < inp.length()-1; i++) {
            if(inp.charAt(i) != inp.charAt(i+1))
                sb_len++;
            else{
                if(sb_len > sb.length())
                    sb = new StringBuffer(inp.substring(i-sb_len+1,i+1));
                sb_len = 1;
            }
        }
        if(sb_len > sb.length())
            sb = new StringBuffer(inp.substring(inp.length()-sb_len,inp.length()));
        
        if(sb.length() < 3)
            return "";
        if(sb_len == inp.length())
            return inp;
        System.out.println(sb);
        return sb.toString();
    }
}

思路如下：

        1.首先定义临时变量sb_len以及可变字符串sb

        2.遍历字符串找到最长的神奇数列即可

        3.返回时要注意条件