#include <string> class Solution { public: string compressString(string param) { int n = param.size(); string ret; int count=0,left=0,right=0; while(right<n) { ret += param[left]; while(right<n && param[left]==param[right]) { count++; right++; } if(count>1) { ret += to_string(count); } count = 0; left = right; } return ret; } };