#include<iostream>
#include<algorithm>
#include<cstdlib>
#include<cstring>
#include<cstdio>
#include<vector>
#include<cmath>
#include<queue>
#include<stack>
#include<deque>
#include<map>
#include<set>
#define MAX(a,b) (a>b?a:b)
#define MIN(a,b) (a<b?a:b)
#define UP upper_bound
#define LB lower_bound
#define LL long long
#define Pi 3.14159265358
#define si size()
#define en end()
#define be begin()
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define ii set<int>::iterator
#define Tree int ind, int L, int R
#define Left 2*ind,L,(L+R)/2
#define Right 2*ind+1,(L+R)/2+1,R
using namespace std;
int Z[40];
int n, m, k, i, j, a, b, res;
vector < int > v, g;
main(){
       //freopen("A.in","r",stdin);
       //freopen("A.out","w",stdout);
       cin>>n>>a>>b;
       if(a==(1<<n)/2 && b==(1<<n)/2){ cout<<1; return 0; }
       while(a)
        {
         v.pb(a%2);
         a/=2;
        }
       while(b)
        {
         g.pb(b%2);
         b/=2;
        }
       for(i=0;i<v.si;i++)
         if(v[i]==1)
           Z[i]++;
       for(i=0;i<g.si;i++)
         if(g[i]==1)
           Z[i]++;
       for(i=n;i>=0;i--)if(Z[i])j=i;
       for(i=n;i>j;i--)if(Z[i]==2)res++;
       res+=n-j;
       cout<<res;
       cin>>n;
       }