#include<cstdio>
#define RI register int
#define CI const int&
using namespace std;
const int N=1e7+5,mod=998244353;
int n,a,b,fact[N<<1],inv[N<<1],ans;
inline void inc(int& x,CI y)
{
	if ((x+=y)>=mod) x-=mod;
}
inline int sub(CI x,CI y)
{
	int t=x-y; return t<0?t+mod:t;
}
inline int quick_pow(int x,int p=mod-2,int mul=1)
{
	for (;p;p>>=1,x=1LL*x*x%mod) if (p&1) mul=1LL*mul*x%mod; return mul;
}
inline void init(CI n)
{
	RI i; for (fact[0]=i=1;i<=n;++i) fact[i]=1LL*fact[i-1]*i%mod;
	for (inv[n]=quick_pow(fact[n]),i=n-1;~i;--i) inv[i]=1LL*inv[i+1]*(i+1)%mod;
}
inline int C(CI n,CI m)
{
	if (n<m) return 0; return 1LL*fact[n]*inv[m]%mod*inv[n-m]%mod;
}
int main()
{
	RI i; scanf("%d%d%d",&n,&a,&b); if (!b) return puts("1"),0;
	for (init(n<<1),i=0;i<=n-b&&i<=a;++i)
	{
		int ret=sub(C(b-1+i,b-1),C(b-1+i,b));
		if (i==n-b) inc(ans,i==a?ret:0); else inc(ans,1LL*ret*C(n-b-i-1+a-i,a-i)%mod);
	}
	return printf("%d",ans),0;
}