Monistus

input/code.cpp: In function 'bool isClear(std::string)':
input/code.cpp:10:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   10 |         for(int i=0;i<s.size();i++){
      |                     ~^~~~~~~~~
input/code.cpp: In function 'std::string solve(std::string)':
input/code.cpp:20:22: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   20 |         for(int i=0;i<s.size();i++){//O(n)
      |                     ~^~~~~~~~~
input/code.cpp:21:39: error: expected ')' before '{' token
   21 |                 if(isDigit(s[i]&&!vst){
      |                   ~                   ^
      |                                       )
input/code.cpp:29:9: error: expected primary-expression before '}' token
   29 |         }
      |         ^

#include<bits/stdc++.h>
using namespace std;
string str;

bool isDigit(char c){
	return c>='0'&&c<='9';
}

bool isClear(string s){
	for(int i=0;i<s.size();i++){
		if(isDigit(s[i]))return false;
	}
	return true;
}

bool vst=false;

string solve(string s){
	string result="";
	for(int i=0;i<s.size();i++){//O(n)
		if(isDigit(s[i]&&!vst){
			int m=s[i]-'0';
			result+=s.substr(i+1,m);
			vst=true
		}
		else{
			result+=s[i];
		}
	}
	return result;
}

int main(){
	cin>>str;
	
	while(!isClear(str)){//O(n)
		vst=false;
		str=solve(str);
	}
	
	cout<<str<<endl;
	
	
	return 0;
}