#include<bits/stdc++.h>
#define ll long long
#define ss second
#define ff first
#define pb push_back
#define endl "\n"
using namespace std;
ll n,cs,cf,dp[2005];
int main(){
ios::sync_with_stdio(false);
cout.tie(0);
cin.tie(0);
cin>>n>>cs>>cf;
for(ll i=1;i<=n;i++){
if(i==cs || i==cf){continue;}
dp[i]++;
if(i<cs){
for(ll j=i+1;j<=n;j++){
if(j==cs || j==cf){continue;}
dp[j]+=1;
}
}
else{
for(ll j=i-1;j>=1;j--){
if(j==cs || j==cf){continue;}
dp[j]+=1;
}
}
}ll sum=0;
for(ll i=1;i<=n;i++){
if(i==cs || i==cf){continue;}
sum=max(dp[i],sum);
}
cout<<sum;
}
