0318A_even_odds.cpp

#include <iostream>
#include <algorithm>
#include <array>
#include <vector>
#include <map>
#include <cmath>
using namespace std;
int main()
{

    long long n, k;
    cin >> n >> k;

    if (k <= (n + 1) / 2)
        cout << k * 2 - 1;
    else
        cout << (k - (n + 1) / 2) * 2;

    return 0;
}