string solution(string number, int k) {
    string answer = "";
    while(k > 0){
        bool checker = false;
        for(int i =0 ; i < number.length()-1 ; ++i){
            if ( number[i] < number[i+1]){
                number.erase(i, 1);
                checker = true;
                break;
            }
        }
        if (checker==false)
            number.erase(number.length()-1,1);
        k--;
    }
    return answer = number;
}