C++ miscellaneous MCQ question and answer with solution | C++ Programimg MCQs

#include <iostream>
using namespace std;
class BaseClass 
{
    protected:
    int i;
    public:
    BaseClass(int x) 
    {
        i = x;
    }
    ~BaseClass() 
    {
    }
};
class DerivedClass: public BaseClass 
{
    int j;
    public:
    DerivedClass(int x, int y): BaseClass(y)
    {
        j = x;
    }
    ~DerivedClass() 
    {
    }
    void show() 
    {
        cout << i << " " << j << endl;
    }
};
int main()
{
    DerivedClass ob(3, 4);
    ob.show();
    return 0;
}

#include <iostream>
#include <stack>
using namespace std;
int main ()
{
    stack<int> mystack;
    mystack.push(10);
    mystack.push(20);
    mystack.top() -= 5;
    cout << mystack.top() << endl;
    return 0;
}

#include <iostream>
#include <functional>
#include <algorithm>
using namespace std;
int main () 
{
    int numbers[] = {1, 2, 3};
    int remainders[5];
    transform ( numbers, numbers + 5, remainders, 
    bind2nd(modulus<int>(), 2) );
    for (int i = 0; i < 5; i++)
        cout << (remainders[i] == 1 ? "odd" : "even") << "\n";
    return 0;
}

#include <new>
#include<cstdlib>
#include <iostream>
using namespace std;
class X;
struct Node 
{
    X* data;
    bool filled;
    Node() : filled(false) { }
};
class X 
{
    static Node buffer[];
    public:
    int number;
    enum { size = 3};
    void* operator new(size_t sz) throw (const char*)
    {
       void* p = malloc(sz);
        if (sz == 0)
            throw "Error: malloc() failed";
        cout << "X :: operator new(size_t)" << endl;
        return p;
    }
    void *operator new(size_t sz, int location) throw (const char*) 
    {
        cout << "X :: operator new(size_t, " << location < ")" << endl;
        void* p = 0;
        if (location < 0 || location >= size || buffer[location].filled == true)
        {
            throw "Error: buffer location occupied";
        }
        else 
        {
            p = malloc(sizeof(X));
            if (p == 0) 
                throw "Error: Creating X object failed";
            buffer[location].filled = true;
            buffer[location].data = (X*) p;
        }
        return p;
    }
    static void printbuffer() 
    {
        for (int i = 0; i < size; i++) 
        {
            cout << buffer[i].data->number << endl;
        }
    } 
};
Node X::buffer[size];
int main()
{
    try 
    {
        X* ptr1 = new X;
        X* ptr2 = new(0) X;
        X* ptr3 = new(1) X;
        X* ptr4 = new(2) X;
        ptr2->number = 10000;
        ptr3->number = 10001;
        ptr4->number = 10002;
        X :: printbuffer();
        X* ptr5 = new(0) X;
    }
        catch (const char* message) 
    {
        cout << message << endl;
    }
 }

#include <iostream>
#include <complex>
using namespace std;
int main()
{
    complex <double> cn(3.0, 5.0);
    cout<<arg(cn)<<endl;
    return 0;
}

#include <iostream>
#include <string>
#include <tuple>
using namespace std;
int main()
{
	tuple <int, char, string> tp;
	tp = make_tuple(4, '1', "Hello");
	cout<<get<0>(tp)<<endl;
	cout<<get<1>(tp)<<endl;
	cout<<get<2>(tp)<<endl;
	return 0;
}