c++ - 从选择的语句中删除选择

Question

基本上我想要做的是让用户输入 1-3 之间的数字，当输入该数字时，if 语句 将执行..

但是，我希望这个循环遍历所有 cookie(它确实如此)，直到每个人都被选中并且不能选择相同的数字。如果您查看我的代码并能解释我应该怎么做，将不胜感激？

#include <iostream>
#include <ctime>
#include <cstdlib>

using namespace std;

int main()
{
    string luck;
    int cookies = 3;
    int choice;
    int *taken;

    for (int i = 0; i < 3; i++) {

        cout << "What cookie do you want?";
        cin >> choice;

        if (choice == 1) {
            cout << "Tomorrow is a day";
        }
        if (choice == 2) {
            cout << "Tomorrow can be cool";
        }
        if (choice == 3) {
            cout << "Summer is coming";
        }
        choice--; //not working though, something wrong im doing i guess.
    }
    return 0;
}

Answer 1

您需要一个容器来跟踪已采取的措施。例如:

#include <iostream>
#include <ctime>
#include <cstdlib>
#include <map>
#include <string>
#include <algorithm>

using namespace std;

int main()
{
    string luck;
    int choice;
    std::map< int, std::string > cookies {
       { 1, "Tomorrow is a day" },
       { 2, "Tomorrow can be cool" },
       { 3, "Summer is coming" }
    };

    while( cookies.size() ) {
        cout << "What cookie do you want? [";
        for_each( cookies.begin(), cookies.end(), []( std::map< int, string >::value_type & v ) { cout << v.first << ','; } );
        cout << ']';
        cin >> choice;

        std::map< int, std::string >::iterator iter( cookies.find( choice ) );
        if( iter == cookies.end() )
            cout << "Sorry, that cookie has been taken" << endl;
        else {
            cout << iter->second << endl;
            cookies.erase( iter );
        }
    }
    return 0;
}