#include <bits/stdc++.h>
using namespace std;
//#define int long long
#define mp make_pair
#define inf 1e9
#define pii pair <int, int>
const int mod = 998244353;
inline int read () {
	int x = 0, f = 1;
	char ch = getchar ();
	while (ch < '0' || ch > '9') f = ((ch == '-') ? -1 : f), ch = getchar ();
	while (ch >= '0' && ch <= '9') x = x * 10 + ch - '0', ch = getchar ();
	return x * f;
}
inline void write (int x) {
	if (x < 0) x = -x, putchar ('-');
	if (x >= 10) write (x / 10);
	putchar (x % 10 + '0');
}
inline int quickmod (int x, int y) {
	int Ans = 1;
	while (y) {
		if (y & 1) Ans = (1ll * Ans * x) % mod;
		x = (1ll * x * x) % mod;
		y >>= 1;
	}
	return Ans;
}
inline void Add(int &x, int y) {
	x += y;
	if(x >= mod) x -= mod;
}
inline int add(int x, int y) {
	x += y;
	if(x >= mod) x -= mod;
	return x;
}
const int B = 800;
int n, c;
namespace Sub1 {
	const int BL = 3000;
	int f[BL+5][2*B+5][2];
	int solve() {
		int Ans = 0;
		for(int i = 1; i <= B; i++) f[i][i][0] = 1;
		int lst = 1, fl = 0;
		for(int L = 1; L <= n; fl ^= 1) {
			int R = min(n, L + BL - 1);
			for(int i = 0; i <= BL + 1; i++) for(int j = 1; j <= 2 * B; j++) f[i][j][fl^1] = 0;
			for(int i = L; i <= R; i++) {
				for(int j = 1; j <= 2 * B; j++) {
					if(j != 1 && i + j - 1 <= n) {
						if(i + j - 1 <= R) Add(f[(i-L+1)+j-1][j-1][fl], 1ll * f[i-L+1][j][fl] * c % mod);
						else Add(f[(i-R)+j-1][j-1][fl^1], 1ll * f[i-L+1][j][fl] * c % mod);
					}
					if(i + j + 1 <= n) {
						if(i + j + 1 <= R) Add(f[(i-L+1)+j+1][j+1][fl], f[i-L+1][j][fl]);
						else Add(f[(i-R)+j+1][j+1][fl^1], f[i-L+1][j][fl]);
					}
				}	
			}
			lst = L, L = R + 1;
		}
		for(int i = 1; i <= 2 * B; i++) Add(Ans, f[n-lst+1][i][fl^1]);
		return Ans;
	}
};//fr <= B
namespace Sub2 {
	int f[2][600005];
	const int AD = 300000;
	int solve() {
		int Ans = (n > B);
		f[0][AD] = 1;
		for(int len = 1, fl = 0; len <= 1000; len++, fl ^= 1) {
			for(int i = 0; i <= 2 * AD; i++) f[fl^1][i] = add((i >= len) ? f[fl][i-len] : 0, (i + len <= 2 * AD) ? 1ll * f[fl][i+len] * c % mod : 0);
			for(int i = B + 1; i <= n; i++) {
				int j = n - (len + 1) * i + AD;
				if(j >= 0 && j <= 2 * AD) Add(Ans, f[fl^1][j]);
			}
		}
		return Ans;
	}
};//fr > B, len < n / B
signed main () {
//	freopen (".in", "r", stdin);
//	freopen (".out", "w", stdout);
	n = read(), c = read();
	write(add(Sub1 :: solve(), Sub2 :: solve())), putchar('\n');
	return 0;
}
/*
300000 114514
*/