class Solution {
public String solution(String code) {
String answer = "";
Boolean mode = false;
for(int i = 0; i < code.length(); i++){
if(code.charAt(i) == '1' && !mode){
mode = true;
}else if(code.charAt(i) == '1' && mode){
mode = false;
}
if (i % 2 == 0 && !mode && code.charAt(i) != '1') {
answer += code.charAt(i);
}else if( i % 2 == 1 && mode && code.charAt(i) != '1') {
answer += code.charAt(i);
}
}
if(answer == ""){
return "EMPTY";
}
return answer;
}
}