某势科技笔试题

某势科技笔试题

输入一个串"PUSH -100;POP 1;PUSH -10;PUSH 20;PUSH 30;POP 2"，输出模拟栈的结果。PUSH XX表示把XX压栈，POP XX表示从栈中弹出XX个数。输出结果。

#include 
using namespace std;

const string PUSH = "PUSH";
const string POP = "POP";

vector<string> stringSplit(string& str, const char split)
{
    vector<string> res;
	istringstream iss(str);
	string token;
	while (getline(iss, token, split))
	{
		res.push_back(token);
	}
    return res;
}

vector<int> interpreStatement(string& statement)
{
    vector<int> res;
    stack<int> stk;
    vector<string> state_arr = stringSplit(statement, ';');
    for (auto&& elem : state_arr)
    {
        vector<string> state_arr_kv = stringSplit(elem, ' ');
        if (state_arr_kv.at(0) == PUSH)
        {
            stk.push(atoi(state_arr_kv.at(1).c_str()));
        }
        else if (state_arr_kv.at(0) == POP)
        {
            for (int i = 0; i < atoi(state_arr_kv.at(1).c_str()); i++)
            {
                if (stk.empty())
                {
                    break;
                }
                stk.pop();
            }
        }
    }
    while (!stk.empty())
    {
        res.push_back(stk.top());
        stk.pop();
    }
    return res;
}

int main()
{
    string oper_statement;
    getline(cin, oper_statement);
    vector<int> oper_vec = interpreStatement(oper_statement);
    for (auto&& elem : oper_vec)
    {
        cout << elem << " ";
    }
    cout << endl;
    return 0;
}