#include using namespace std; using ll = long long; using ld = long double; using vl = vector; template using vc = vector; template using vvc = vector>; #define eb emplace_back #define all(x) (x).begin(), (x).end() #define rep(i, n) for (ll i = 0; i < (n); i++) #define repr(i, n) for (ll i = (n)-1; i >= 0; i--) #define repe(i, l, r) for (ll i = (l); i < (r); i++) #define reper(i, l, r) for (ll i = (r)-1; i >= (l); i--) #define repa(i,n) for (auto& i: n) template inline bool chmax(T1 &a, const T2 &b) {if (a inline bool chmin(T1 &a, const T2 &b) {if (b void verr(const set &st) { repa(a, st) cerr << a << " "; cerr << endl; } template void verr(const map &mp) { repa(a, mp) cerr << "{" << a.first << ", " << a.second << "} "; cerr << endl; } template void verr(const vector>& a, const N& n) { rep(i, n) cerr << "{" << a[i].first << ", " << a[i].second << "} "; cerr << endl; } template void verr(const vector& a, const N& n) { rep(i, n) cerr << a[i] << " "; cerr << endl; } ll dbgt = 1; void err() { cerr << "passed " << dbgt++ << endl; } template void err(H&& h,T&&... t){ cerr<< h << (sizeof...(t)?" ":"\n") << flush; if(sizeof...(t)>0) err(forward(t)...); } #endif const ll INF = 4e18; const ld EPS = 1e-11; const ld PI = acos(-1.0L); // const ll MOD = 1e9 + 7; const ll MOD = 998244353; //--------------------------------------------------------------------------------// // modint template struct modint { long long val; static const int mod = _MOD; modint(long long v = 0) noexcept : val(v % mod) { if (val < 0) val += mod; } inline modint operator - () const noexcept { return val ? mod - val : 0; } inline modint operator + (const modint& r) const noexcept { return modint(*this) += r; } inline modint operator - (const modint& r) const noexcept { return modint(*this) -= r; } inline modint operator * (const modint& r) const noexcept { return modint(*this) *= r; } inline modint operator / (const modint& r) const noexcept { return modint(*this) /= r; } inline modint& operator += (const modint& r) noexcept { val += r.val; if (val >= mod) val -= mod; return *this; } inline modint& operator -= (const modint& r) noexcept { val -= r.val; if (val < 0) val += mod; return *this; } inline modint& operator *= (const modint& r) noexcept { val = val * r.val % mod; return *this; } inline modint& operator /= (const modint& 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; } inline bool operator == (const modint& r) const noexcept { return this->val == r.val; } inline bool operator != (const modint& r) const noexcept { return this->val != r.val; } inline friend ostream& operator << (ostream &os, const modint& x) noexcept { return os << x.val; } inline friend istream& operator >> (istream &is, modint& x) noexcept { is >> x.val; x = modint(x.val); return is; } inline friend modint modpow(const modint &a, long long n) noexcept { modint t = 1, v = a; while(n){ if (n & 1) t *= v; v *= v; n >>= 1; } return t; } }; using mint = modint; int main() { ll N, X, Y; cin >> N >> X >> Y; if (X > Y) swap(X, Y); if(Y - X == 1 and X > 1 and Y < N) { cout << 0 << endl; return 0; } ll n = Y - X - 2; if (X == 1) n++; if (Y == N) n++; vc dp(n + 1); dp[0] = 1; rep(i, n) { dp[i + 1] += dp[i]; if(i + 3 <= n) dp[i + 3] += dp[i]; } cout << dp[n] << endl; }