main2.cpp

#ifdef MAIN2
#include <iostream>
using namespace std;

template <class T>
class ShiftedList{
    T *array;
    int offset, size;
public:
    ShiftedList(int sz):offset(0), size(sz){
        array = new T[size];
    }
    ~ShiftedList(){
        delete [] array;
    }

    void shiftBy(int n){
        offset = (offset + n) % size;
    }

    T getAt(int i){
        return array[convertIndex(i)];
    }

    void setAt(T item, int i){
        array[convertIndex(i)] = item;
    }

private:
    int convertIndex(int i){
        int index = (i - offset) % size;
        while(index < 0){
            index += size;
        }
        return index;
    }
};

int main()
{
    int size = 4;
    ShiftedList<int> *list = new ShiftedList<int>(size);
    for(int i = 0; i < size; i++){
        list->setAt(i, i);
    }
    cout << list->getAt(0) << endl;
    cout << list->getAt(1) << endl;
    list->shiftBy(1);
    cout << list->getAt(0) << endl;
    cout << list->getAt(1) << endl;
    delete list;
    return 0;
}
#endif