bool all_are_doubles(string words, int length){
map<char, bool> map;
for(int i=0; i<=length-1; i++){
map[words[i]] = !(map[words[i]]);
}
for(auto i = map.begin(); !(i == map.end()); i++){
while(i->second){
return 0;
}
}
return 1;
}
