//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,avx2")
//#pragma GCC optimize("Ofast","unroll-loops","inline")
#include<bits/stdc++.h>
#define ll long long
//#define int ll
#define pb push_back
#define pii pair<int,int>
#define MP make_pair
#define fi first
#define se second
using namespace std;
const int N=1e6+10,M=1e6+10,mod=998244353;
inline void Add(int &x,int y){x+=y;if(x>=mod) x-=mod;}
inline void Del(int &x,int y){x-=y;if(x<0) x+=mod;}
inline int del(int x,int y){x-=y;return x<0?x+mod:x;}
inline int add(int x,int y){x+=y;return x>=mod?x-mod:x;}
int qpow(int a,int b){
	int res=1;
	while(b){
		if(b&1) res=1ll*res*a%mod;
		a=1ll*a*a%mod;b>>=1;
	}return res;
}
int n,m,f[N],g[N],pw[N],ipw[N];
signed main(){
	ios::sync_with_stdio(false);cin.tie(0);cout.tie(0);
	cin>>n>>m;
	int im=qpow(m,mod-2);
	pw[0]=ipw[0]=1;
	for(int i=1;i<=n;i++) pw[i]=1ll*pw[i-1]*m%mod;
	for(int i=1;i<=n;i++) ipw[i]=1ll*ipw[i-1]*im%mod;
	for(int i=1;i<=n;i++){
		f[i]=1ll*pw[i]*del(1,g[i/2])%mod;
		if(2*i<=n) g[i]=add(g[i-1],1ll*f[i]*ipw[2*i]%mod);
	}
	int ans=0;
	for(int i=1;i<(n+1)/2;i++) Add(ans,1ll*f[i]*pw[n-2*i]%mod);
	cout<<ans<<'\n';
	return 0;
}