10718.cpp

#include <bits/stdc++.h>

using namespace std;

#define MAX(a, b) (a > b ? a : b)

typedef long long ss;

ss A[40], B[40], ind1, ind2, N, L, U, all;

void Binary(ss n, ss a[], ss &ind)
{
	ind = 0;
	all = 1;
	while (n)
	{
		a[ind++] = n % 2;
		if (a[ind - 1] == 0)
			all = 0;
		n /= 2;
	}
}
void Rev(ss a[], ss n)
{
	ss temp[40], i, j = 0;
	for (i = n - 1; i >= 0; i--)
		temp[j++] = a[i];
	for (i = 0; i < n; i++)
		a[i + 1] = temp[i];
}
int Recur(ss limit, ss level, ss sum)
{
	ss x, y, z;
	x = limit - level + 1;
	y = (ss)pow(2, (double)x) - 1;
	if (sum > U)
		return 0;
	if (sum + y < L)
		return 0;
	if (level == limit + 1 && sum <= U)
	{
		printf("%lld\n", sum);
		return 1;
	}
	if (A[level] == 0)
	{
		z = sum + (ss)pow(2, double(limit - level));
		if (Recur(limit, level + 1, z))
			return 1;
		if (Recur(limit, level + 1, sum))
			return 1;
	}
	if (A[level] == 1)
	{
		if (Recur(limit, level + 1, sum))
			return 1;
		z = sum + (ss)(pow(2, (double)(limit - level)));
		if (Recur(limit, level + 1, z))
			return 1;
	}
	return 0;
}
void Cal()
{
	ss max;
	if (U == L)
	{
		printf("%lld\n", L);
		return;
	}
	for (max = 0; max < 35; max++)
		A[max] = 0;
	Binary(N, A, ind1);
	if (all && N >= U)
	{
		printf("%lld\n", L);
		return;
	}
	Binary(U, B, ind2);
	max = MAX(ind1, ind2);
	Rev(A, max);
	Recur(max, 1, 0);
}

int main()
{
	while (scanf("%lld%lld%lld", &N, &L, &U) == 3)
		Cal();
	return 0;
}