#include<bits/stdc++.h>
using namespace std;
/*
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace __gnu_pbds;

typedef tree<int,null_type,less<int>,rb_tree_tag,tree_order_statistics_node_update> ordered_set;
*/
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
uniform_real_distribution<> pp(0.0,1.0);
#define int long long
#define ld long double
#define pii pair<int,int>
#define piii pair<int,pii>
#define mpp make_pair
#define fi first
#define se second
const long long inf=1e18;
const int mod=998244353;
//int mod=998244353;
const int maxn=1000005;
const int B=650;
const int maxs=655;
const int maxm=200005;
const int maxq=1000005;
const int maxl=25;
const int maxa=1000000;
const int root=3;
int power(int a,int n){
    int res=1;
    while(n){
        if(n&1) res=res*a%mod;
        a=a*a%mod;n>>=1;
    }
    return res;
}
const int iroot=power(3,mod-2);
const int base=101;

int fac[maxn],dfac[maxn],inv[maxn],p2[maxn];

void combi(int n){
    fac[0]=p2[0]=1;
    for(int i=1;i<=n;i++) fac[i]=fac[i-1]*i%mod,p2[i]=p2[i-1]*2%mod;
    dfac[n]=power(fac[n],mod-2);
    for(int i=n;i>=1;i--){
        dfac[i-1]=dfac[i]*i%mod;
        inv[i]=dfac[i]*fac[i-1]%mod;
    }
}

int C(int n,int k){
    if(k>n || k<0 || n<0) return 0;
    return fac[n]*dfac[k]%mod*dfac[n-k]%mod;
}

void solve(){
    int n,m;cin >> n >> m;

    vector<int> dp(n+1,0);
    int pw=1,sum=0;
    for(int i=1;i<=n;i++){
        pw=pw*m%mod,sum=sum*m%mod;
        if(i%2==0) sum=(sum+dp[i/2])%mod;
        dp[i]=(pw+mod-sum)%mod;
    }
    int res=dp[n];
    if(!(n&1)) res=(res+dp[n/2]+mod)%mod;
    cout << (pw-res+mod)%mod << '\n';
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);cout.tie(NULL);
    int test=1;//cin >> test;
    while(test--) solve();
}