#include<bits/stdc++.h>
using namespace std;
#define ll long long
#define int long long
#define rep(s,i,n) for(int i=s;i<n;i++)
#define rrep(s,i,n) for(int i=n-1;i>=s;i--)
#define c(n) cout<<n<<endl;
#define cd(d) cout<<setprecision(20)<<d<<endl;
#define ic(n) int n;cin>>n;
#define sc(s) string s;cin>>s;
#define dc(d) double d;cin>>d;
#define CY c("Yes") return 0;
#define CN c("No") return 0;
#define mod 998244353
#define mod2 1000000007
#define inf 2000000000000000000
#define P pair<int,int>
#define f first
#define s second
#define pi 3.141592653589793238462643383279
#define pb push_back
int gcd(int x,int y){
    x=abs(x),y=abs(y);
    if(x==0||y==0)return x+y;
    if(x<y)swap(x,y);
    return gcd(x%y,y);
}
int lcm(int x,int y){
    x=abs(x),y=abs(y);
    return x/gcd(x,y)*y;
}
int pow(int n,int m,int modulo){
    int pro=1;
    int nn=n;
    while(m){
        if(m%2==1)pro=pro*nn%modulo;
        m=m/2;
        nn=nn*nn%modulo;
    }
    return pro;
}
int inv(int n,int m,int modulo){
    int t=pow(m,modulo-2,modulo);
    return n*t%modulo;
}
template<int MOD> struct Fp {
    long long val;
    constexpr Fp(long long v = 0) noexcept : val(v % MOD) {
        if (val < 0) v += MOD;
    }
    constexpr int getmod() { return MOD; }
    constexpr Fp operator - () const noexcept {
        return val ? MOD - val : 0;
    }
    constexpr Fp operator + (const Fp& r) const noexcept { return Fp(*this) += r; }
    constexpr Fp operator - (const Fp& r) const noexcept { return Fp(*this) -= r; }
    constexpr Fp operator * (const Fp& r) const noexcept { return Fp(*this) *= r; }
    constexpr Fp operator / (const Fp& r) const noexcept { return Fp(*this) /= r; }
    constexpr Fp& operator += (const Fp& r) noexcept {
        val += r.val;
        if (val >= MOD) val -= MOD;
        return *this;
    }
    constexpr Fp& operator -= (const Fp& r) noexcept {
        val -= r.val;
        if (val < 0) val += MOD;
        return *this;
    }
    constexpr Fp& operator *= (const Fp& r) noexcept {
        val = val * r.val % MOD;
        return *this;
    }
    constexpr Fp& operator /= (const Fp& r) noexcept {
        long long a = r.val, b = MOD, u = 1, v = 0;
        while (b) {
            long long t = a / b;
            a -= t * b; swap(a, b);
            u -= t * v; swap(u, v);
        }
        val = val * u % MOD;
        if (val < 0) val += MOD;
        return *this;
    }
    constexpr bool operator == (const Fp& r) const noexcept {
        return this->val == r.val;
    }
    constexpr bool operator != (const Fp& r) const noexcept {
        return this->val != r.val;
    }
    friend constexpr ostream& operator << (ostream &os, const Fp<MOD>& x) noexcept {
        return os << x.val;
    }
    friend constexpr istream& operator >> (istream &is, Fp<MOD>& x) noexcept {
        return is >> x.val;
    }
    friend constexpr Fp<MOD> modpow(const Fp<MOD> &a, long long n) noexcept {
        if (n == 0) return 1;
        auto t = modpow(a, n / 2);
        t = t * t;
        if (n & 1) t = t * a;
        return t;
    }
};
using mint=Fp<mod>;
struct comb{
    vector<mint> fac,invfac;
    comb(int n){
        fac.pb(1);
        rep(1,i,n+1)fac.pb(fac[i-1]*i);
        rep(0,i,n+1){
            invfac.pb(1);
            invfac[i]/=fac[i];
        }
    }
    mint com(int n,int m){
        if(n<m)return 0;
        else return fac[n]*invfac[m]*invfac[n-m];
    }
};
using graph=vector<vector<int>>;
graph makeG(int n,int m,vector<int> u,vector<int> v,bool d){
    graph G(n);
    rep(0,i,m){
        G[u[i]].pb(v[i]);
        if(d)G[v[i]].pb(u[i]);
    }
    return G;
}
struct UF{
    vector<int> par,rank,siz;
    UF(int n):par(n,-1),rank(n,0),siz(n,1){}
    int root(int x){
        if(par[x]==-1)return x;
        else return par[x]=root(par[x]);
    }
    bool  same(int x,int y){
        return root(x)==root(y);
    }
    bool unite(int x,int y){
        int rx=root(x),ry=root(y);
        if(rx==ry)return false;
        if(rank[rx]<rank[ry])swap(rx,ry);
        par[ry]=rx;
        if(rank[rx]==rank[ry])rank[rx]++;
        siz[rx]+=siz[ry];
        return true;
    }
    int size(int x){
        return siz[root(x)];
    }
};
graph makeUF(int n,graph g){
    UF d(n);
    vector<vector<int>> m(n);
    rep(0,i,n){
        for(auto t:g[i])d.unite(i,t);
    }
    rep(0,i,n)m[d.root(i)].pb(i);
    return m;
}
using wgraph=vector<vector<P>>;
vector<int> dijstra(int n,wgraph g,int st,bool d){
}
signed main(){
    ic(n) ic(m)
    if(n<m)swap(n,m);
    if(m*2<n)c(n-m*2)
    else c((n+m)%2)
}