#include <iostream>
#include <tchar.h>

int _tmain(int argc, _TCHAR* argv[])
{
    char c[4];
    c[0]='a';
    c[1]='b';
    c[2]='c';
    c[3]='d';

    std::cout << "before: " << c[0] << c[1] << c[2] << c[3] << std::endl;
    
    for (int n=2 ; n>0; --n)
    {
        for (int i=0; i<3; i++)
        {
            c[i] = c[i+1];
        }
        c[3] = 'x';
    }

    std::cout << "after: " << c[0] << c[1] << c[2] << c[3] << std::endl;
    return 0;
}