//Check for different numbers
int check(int *a,int f,int k,int n)
{
    for(int i=f;i<k;i++)
    {
        if (a[i]==a[k]) return 1;
    }
    return 0;
}
//Generate all the permutations of a[k]..a[n-1]
//a is an array and n is the lenght of the array
//k is the statrting index for generating permutations
void p(int *a,int k,int n)
{
    if(k==n-1)
    {
        for(int i=0;i<n;i++)
        {
            Console::Write(a[i]);
        }
        Console::WriteLine();
    }
    else
    {
        for(int i=k;i<n;i++)
        {
                      //if this value differs others generate permutations
                       if(!check(a,k,i,n))
                {
            int temp=a[k];a[k]=a[i];a[i]=temp;
            p(a,k+1,n);
            temp=a[k];a[k]=a[i];a[i]=temp;
                }

        }
    }
}
int _tmain()
{
    int a[4];
    a[0]=1;//optional,two times H and two times T
    a[1]=0;
    a[2]=0;
    a[3]=1;
    p(a,0,4);
    Console::Read();
    return 0;
}