用了前缀和优化，但是丝毫不知道哪里挂掉了啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊啊

就一直 WA 4 个点。。。。。。。。。。。。。。。。。。

#include<cstdio>
#include<cmath>
#include<algorithm>
#include<queue>
#include<vector>
#include<cstring>
#include<ctime>
#include<cstdlib>
#include<cctype>
#include<stack>
#include<map>
#include<climits>
#include<set>
#include<iostream>
#define rint() read<int>()
#define rll() read<ll>()
#define rep(i,a,b) for(register int i=a;i<=b;++i)
#define rev(i,a,b) for(register int i=a;i>=b;--i)
#define gra(i,u) for(register int i=head[u];i;i=edge[i].nxt)
#define Clear(a) memset(a,0,sizeof(a))
using namespace std;
typedef long long ll;
inline int read()
{
	register int s=0,w=1;
	char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')w=-1;ch=getchar();}
	while(ch>='0'&&ch<='9')s=s*10+(ch-'0'),ch=getchar();
	return s*w;
}
const int INF=1e9;
const ll LLINF=1e18;
template<typename T>
inline T Min(T x,T y){return x<y?x:y;}
template<typename T>
inline T Max(T x,T y){return x>y?x:y;}
template<typename T>
inline void Swap(T&x,T&y){int t=x;x=y;y=t;return;}
int n,m,k;
const int MAXN(1010);
const int MAXM(5010);
const int MOD(998244353);
inline int add(int x,int y){return (x+y)%MOD;}
int dp[MAXM][MAXM];
int sum[MAXM];
int main()
{
	n=read(),m=read(),k=read();
	rep(i,1,m) dp[1][i]=1;
	rep(i,1,m) sum[i]=add(sum[i-1],dp[1][i]);
	rep(i,2,n)
	{
		rep(j,1,m)
		{
			if(k+j<=m) dp[i][j]=add(dp[i][j],(sum[m]-sum[k+j-1]+MOD)%MOD);
			if(j-k>=1) dp[i][j]=add(dp[i][j],sum[j-k]);
		}
		rep(j,1,m) sum[j]=add(sum[j-1],dp[i][j]);
	} 
	printf("%d\n",sum[m]);
	return 0;
}