#include <bits/stdc++.h>

using namespace std;

long long pw2[100];

int divide(int x, int y, int dim) {

    if (dim == 0) {
        return 0;
    } 

        if (x <= pw2[dim - 1] && y <= pw2[dim - 1] ) {

            return divide(y, x, dim - 1);
        } 

        if (x > pw2[dim - 1] && y <= pw2[dim - 1]) {

            return pw2[dim - 1] * pw2[dim - 1] + divide(x - pw2[dim - 1], y, dim - 1);
        }

        if (x > pw2[dim -1] && y > pw2[dim - 1]) {

            return 2 * pw2[dim - 1] * pw2[dim - 1] + divide(x - pw2[dim - 1], y - pw2[dim - 1], dim - 1);
        }

        return 3 * pw2[dim - 1] * pw2[dim - 1] + divide(pw2[dim - 1] - y  + pw2[dim - 1] + 1, pw2[dim - 1] - x + 1, dim - 1);
        
    

    
    
}

int main()
{

    ifstream f("fractal.in");
    ofstream g("fractal.out");
    pw2[0] = 1;
    int x, y, k;

    
    f >> k >> x >> y;
    for (int i = 1; i <= 30; i++) {
        pw2[i] = 2 * pw2[i - 1];
        //cout << pw2[i] << endl;
    }
    g << divide(x, y, k);
}