火车组成的C 样品测试

Question

我已经修改了下面的代码，以进行样本测试，如https://www.testdome.com/for-developers/solve-question/9930

"通过将货车从左侧和右侧连接和脱离货车来构建火车。例如，如果我们从左侧固定货车7开始，然后将货车13安装，则从左侧再次将货车(从左到右(获得两辆货车的组成(13和7(。现在，可以从右侧脱离的第一辆车是7，而第一辆可以从左边脱离的货车为13。实施对这个问题进行建模的火车记录。"

#include <stdexcept>
#include <iostream>
#include <vector>
class TrainComposition
{
    //std::vector<int> wagons;
    public:
    std::vector<int> wagons;
    void attachWagonFromLeft(int wagonId)
    {
        wagons.insert(wagons.begin(), wagonId);
    }
    void attachWagonFromRight(int wagonId)
    {
        wagons.push_back(wagonId);
    }
    int detachWagonFromLeft()
    {
        int ret = wagons[0];
        wagons.erase(wagons.begin());
        return ret;
    }
    int detachWagonFromRight()
    {
        int ret = wagons[(int)(wagons.size()) - 1];
        wagons.pop_back();
        return ret;
    }
};
#ifndef RunTests
int main()
{
    TrainComposition tree;
    tree.attachWagonFromLeft(7);
    tree.attachWagonFromLeft(13);
    std::cout << tree.detachWagonFromRight() << "n"; // 7 
    std::cout << tree.detachWagonFromLeft() << "n";; // 13
    return 0;
}
#endif

测试结果失败了具有大量货车的性能测试：超过时间限制

请帮助解决此失败...

Answer 1

这是我解决此问题的示例代码：

#include <stdexcept>
#include <iostream>
#include <deque>
class TrainComposition
{
public:
    std::deque<int> my_train;
    void showdq() 
    { 
        std::deque <int> :: iterator it; 
        for (it = my_train.begin(); it != my_train.end(); ++it) 
        std::cout << 't' << *it; 
        std::cout << 'n'; 
    } 
    void attachWagonFromLeft(int wagonId)
    {
        //std::cout << "Attaching Wagon " << wagonId << " from left!"<< std::endl;
        my_train.push_front(wagonId);
    }
    void attachWagonFromRight(int wagonId)
    {
        //std::cout << "Attaching Wagon " << wagonId << " from right!"<< std::endl;
        my_train.push_back(wagonId);
    }
    int detachWagonFromLeft()
    {
        int detachedWagon = my_train.front();
        my_train.pop_front();
        return detachedWagon;
    }
    int detachWagonFromRight()
    {
        int detachedWagon = my_train.back();
        my_train.pop_back();
        return detachedWagon;
    }
};
#ifndef RunTests
int main()
{
    TrainComposition tree;
    //tree.attachWagonFromLeft(1);
    //tree.attachWagonFromLeft(2);
    tree.attachWagonFromLeft(7);
    tree.attachWagonFromLeft(13);
    //std::cout << "Train's Wagon: ";
    //tree.showdq();
    std::cout << "Detaching " << tree.detachWagonFromRight() << " from rightn"; // 7 
    std::cout << "Detaching "<< tree.detachWagonFromLeft() << " frim leftn"; // 13
    //std::cout << "Train's Wagon After: ";
    //tree.showdq();
}
#endif

这是我得到的结果：

Compilation OK
Detaching 7 from right
Detaching 13 frim left 
Your score is 100%, perfect!

请注意使用std::cout(上面的摘要(打印可能会导致以下结果：

Performance test with a large number of wagons: Time limit exceeded
Your score is 67%, nice!