#include <string>
class Solution {
  public:
    /**
     * 代码中的类名、方法名、参数名已经指定,请勿修改,直接返回方法规定的值即可
     *
     *
     * @param param string字符串
     * @return string字符串
     */
    string compressString(string param) {
        // write code here
        if(param.empty()){
            return param;
        }


        string str = param;
        // string str_tmp = str;
        string str_tmp;
        int cnt = 1;
        for (int i = 0; i <= str.size() - 1; i++) {
            if (str[i + 1] == str[i]) {
                cnt++;
            } else {
                if (cnt != 1) {
                    str_tmp += str[i];
                    string str_num = std::to_string(cnt);
                    str_tmp += str_num;
                    cnt = 1;
                }else{
                    str_tmp+=str[i];
                    cnt=1;
                }

            }
        }

        return str_tmp;
    }

};