#include <bits/stdc++.h>
using namespace std;

int main() {
    int n, k;
    cin >> n >> k;
    int ans = 0;
    if(2 * k + 1 <= n) ans = (2 * k + 1) / 2 + 1;
    else {
        int low = (-k) % n;
        int high = k % n;
        if(low < 0) low += n;
        if(abs(low - high) % 2 == 0) {
            ans = n / 2;
            if(k % 2 == 0 && n % 2 == 1) ans++;
        }
        else ans = min(n, (2 * k + 1) / 2 + 1);
    }

    cout << ans << endl;;
}