#include <bits/stdc++.h>
#define pii pair<int, int>

using namespace std;
ifstream f("fractal.in");
ofstream g("fractal.out");
long long N, K, x, y;
long long solve (long long sz, long long x, long long y)  { // MA FUT IN CINE A FORMULAT PROBLEMA ASTA IDIOATA
    if (sz == 1) return 0;
    long long mid = sz / 2;
    long long adaos = mid * mid;
    if (x < mid && y < mid) {
        return solve(mid, y, x);
    }
    else if (x < mid && y >= mid) {
        return  adaos + solve(mid, x, y - mid);
    }
    else if (x >= mid && y < mid) {
        return 3 * adaos + solve(mid, mid - y - 1, 2 * mid - x - 1);
    }
    else return 2 * adaos + solve(mid, x - mid, y - mid);
}
int main() {
    f >> N >> x >> y;
    g << solve((1LL << N), x - 1, y - 1) << '\n';
}