unsigned long long A,B,C,D,E,F,    I,J,K,  M,N,O,P,Q,R,S,T,U,V,  X,Y,Z;
	//long long A,B,C,D,E,F,  H,I,J,K,L,M,N,O,P,Q,R,S,T,U,V,W,X,Y,Z;
	double dA,dB,dC,dD,dE,dF,   dI,dJ,dK,  dM,dN,dO,dP,dQ,dR,dS,dT,dU,dV,  dX,dY,dZ;
	#include <string>
	#include <bits/stdc++.h>
	using namespace std;
	typedef long long ll;
	#include <iostream>
	#include <algorithm>
	#include <vector>
	#include <queue>
	#include <string>
	#include <iomanip>
	#include <cmath>

	//typedef pair<long long,long long> P;
	//typedef pair<long long,P> P1;
	//typedef pair<P,P> P2;
	#define pu push
	#define pb push_back
	#define mp make_pair
	#define eps 1e-7
	//#define INF 100000000000000000//19桁
	#define INF 1e18+5//19桁
	#define mod 1000000007
	#define fi first
	#define se second
	#define rep(i,x) for(long long i=0;i<x;i++)
	#define repn(i,x) for(long long i=1;i<=x;i++)
	#define REP(i,n,x) for(long long i=n;i<x;i++)
	#define REPN(i,n,x) for(long long i=n+1;i<x;i++)
	#define repn(i,x) for(long long i=1;i<=x;i++)
	#define rrep(i,x) for(long long i=x-1;i>=0;i--)
	#define rrepn(i,x) for(long long i=x;i>1;i--)
	#define SORT(x) sort(x.begin(),x.end())
	#define ERASE(x) x.erase(unique(x.begin(),x.end()),x.end())
	#define POSL(x,v) (lower_bound(x.begin(),x.end(),v)-x.begin())
	#define POSU(x,v) (upper_bound(x.begin(),x.end(),v)-x.begin())
	#define All(x) (x).begin(),(x).end()
	#define rAll(x) (x).rbegin(),(x).rend()

	#define ALL(v)  (v).begin(),(v).end()
	//#define MAX(a,b) if(a>b)
	#define MAX(a,b) (((a)>(b))?(a):(b))
	#define MIN(a,b) (((a)<(b))?(a):(b))
	#define popcount __builtin_popcount

	const string MINUSINF = "-";

	template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
	void chmax(string &a, string b) {
		if (a == MINUSINF) a = b;
		else if (a.size() < b.size()) a = b;
		else if (a.size() == b.size()) {
			if (a < b) a = b;
		}
	}


	template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }

	#define pr printf
	#define re return
	#define CASET int ___T, case_n = 1; scanf("%d ", &___T); while (___T-- > 0)


	int GCD(int a, int b) { return b ? GCD(b, a%b) : a; }

	stack<long long> sta;   
	queue<long long> que;
	deque<long long> dque;

	set <string> s_set;








	long long sum,sum1,sum2,sum3,sum4;
	long long flg,flg1,flg2,flg3,cnt,cnt1,cnt2,cnt3,cnt4;
	long long wk,wk1,wk2,wk3,wk4;
	long long ans;

	double dsum,dsum1,dsum2,dsum3,dsum4;
	double dcnt,dcnt1,dcnt2,dcnt3,dcnt4;
	double dwk,dwk1,dwk2,dwk3,dwk4;
	double dans;
	double dmax,dmax1;
	double dmin,dmin1;



	bool f;

	long long weight[110], value[110]; // 品物の個数は 100 個なので少し余裕持たせてサイズ 110 に
	ll a[100010][3]; // a[i], b[i], c[i] をそれぞれまとめて a[i][0], a[i][1], a[i][2] にしてしまう
	long long n,h[100005];
	vector<long long> p, c;
	int vis[200001];

	vector<string> fi;
	int Left[2100][2100], Right[2100][2100], Up[2100][2100], Down[2100][2100];

	long long match[10] = {2,5,5,4,5,6,3,7,6};
	vector<long long> box;



	int main(){
		
		cin.tie(nullptr);
		ios::sync_with_stdio(false);

		long long max,max1;
		long long min,min1;
		

		sum=sum1=sum2=sum3=sum4=0;
		flg=flg1=flg2=flg3=cnt=cnt1=cnt2=cnt3=cnt4=0;
		max=max1=0;
		wk=wk1=wk2=wk3=wk4=0;
		ans=0;
		min=min1=INF;

		dsum=dsum1=dsum2=dsum3=dsum4=0;
		dcnt=dcnt1=dcnt2=dcnt3=dcnt4=0;
		dmax=dmax1=0;
		dwk=dwk1=dwk2=dwk3=dwk4=0;
		dans=0;
		dmin=dmin1=INF;
		
		

		//**************************こどふぉ用******************************************
		/*
		char c[3]={'R', 'G', 'B'};
		cin >> T;
		while(T--){
			cin >> N >> K;
			//std::vector<long long> v(N);	
			//vector<ll> v(N, 0);
			//set<long long> st;
			//map<std::string, int> freq;
			//map<int,int> M;
			//M.clear();
			
			//if(st.find(v[i])==st.end()){
			//	st.insert(v[i]);
			//}
			//else{
			//	st.erase(v[i]);
			//}
			
			//vector<pair<long long, long long> > p(M);
			//for(long long i=0; i<M; i++){
			//long long a, b;
			//cin >> a >> b;
			//p[i] = make_pair(a, b);
			//}
			//int ret=1<<20;
			
			for(int i=1;i<=N;i++){
				
			}
			cout << N << "\n";
		}
		*/
		
		//**************************ここからスタート******************************************
		//std::cin >> N;
		//std::cin >> N >> M;
		//std::cin >> N >> M >> K;
		//std::cin >> N >> K;
		//std::cin >> A >> B;
		std::cin >> N >> A >> B;
		if(A>B){
			wk=B;
			B=A;
			A=wk;
		}
			if((B-A)%2==0){
				pr("%llu",(B-A)/2);	
			}
			else{
				pr("%llu",MIN((B-A+1)/2+A-1,(B-A+1)/2+N-B));	
			}	
		re 0;
		//std::vector<long long> v(N);
		//std::vector<long long> w(N);
		//std::vector<long long> x(N);
		//std::vector<int> v(100, 0);
		//int a[26]={0};
		//vector<long long> flagment(N, 0);
		
		//v.push_back(i);
		//accumulate(vec.begin(), vec.end(), 0)
		//v.resize
		
		// 配列入力1
		/*
		for(long long i=0; i<N; i++){
			std::cin >> v[i];
		}
		*/
		
		
		//std::sort(v.begin(),v.end());//昇順ソート
		//std::sort(v.begin(),v.end(),std::greater<long long>());//降順ソート
		
		//通常
		/*
		for(long long i=0; i<N; i++){
			
			
			
		}
		*/

		//文字列入力
		/*
		string s,t;
		std::cin >> s;
		//sort(s.begin(), s.end());
		//s=to_string(i);
		for(long long i=0; i<s.length(); i++){
			
			//wk=(s[i+2]-'0')+10*(s[i+1]-'0')+100*(s[i]-'0');
			if(s[i]!='1'){
			}	
		}
		*/

		/*
		if(1){
			printf("%lld",N);
			//printf("%lld",N);
			//puts("Yes");
			//printf("%d",st.size());
			//文字列の出力
			//std::cout << s << std::endl;
			//printf("%.12f\n",ret);
			//cout << sum << endl;
		}
		else{
			//puts("No");
		}
		return 0;
		*/

		
		
		return 0;
	}


Measured memory_bytes: 4352