1.下一个回文数

2.跑步机的使用次数

3.数组转置

4.压缩字符串最短结果输出

import java.util.*;
public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        Solution solution = new Solution();
       String answer =solution.compressString(str);
       System.out.println(answer);
    }
}
class Solution{
        public  String compressString(String S) {
          StringBuffer sb = new StringBuffer();
          int i = 0;
          while (i < S.length()) {
               int j = i + 1;
               while (j < S.length() && S.charAt(i) == S.charAt(j)) {
                j++;
                }
           sb.append(String.valueOf(j - i)+String.valueOf(S.charAt(i)) );
           i = j;
          }
          return sb.toString();
      //sb.toString().length() < S.length() ? sb.toString() : S;
     }
}