#include <iostream>
#include <vector>

int getProgression(const int &n);

int main(void)
{
    const int N = 4;

    int arr[N] = {1, 2, 1, 3};

    std::vector<int> used(10, 0);

    int tmp, summ = 0;

    for (int i = 1; i <= N; ++i)
    {
        tmp = arr[i - 1];
        if (used[tmp] == 0)
        {
            int l = N - i;
            summ += getProgression(l) + l + 1;
        }
        ++used[tmp];
    }

    std::cout << summ << std::endl;


    system("pause");
    return 0;
}


int getProgression(const int &n)
{
    if (n == 2)
        return 1;
    if (n < 2)
        return 0;
    return (((n - 1) / 2) * n) + getProgression(n - 1);
}