# pragma GCC target("avx2")
# pragma GCC optimize("O3")
# pragma GCC optimize("unroll-loops")
#include<atcoder/all>

#include <iostream> // cout, endl, cin
#include <string> // string, to_string, stoi
#include <vector> // vector
#include <algorithm> // min, max, swap, sort, reverse, lower_bound, upper_bound
#include <utility> // pair, make_pair
#include <tuple> // tuple, make_tuple
#include <cstdint> // int64_t, int*_t
#include <cstdio> // printf
#include <map> // map
#include <queue> // queue, priority_queue
#include <set> // set
#include <stack> // stack
#include <deque> // deque #include <unordered_map> // unordered_map #include <unordered_set> // unordered_set #include <bitset> // bitset
#include <cctype> // isupper, islower, isdigit, toupper, tolower
#include <math.h>
#include <iomanip>
#include <functional>
#include<unordered_map>
#include <random>
#include<bitset>
#include<cassert>
#include<chrono>
using namespace std;  
using namespace atcoder;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define repi(i, a, b) for (int i = (int)(a); i < (int)(b); i++)
#define endl '\n'
#define all(x) (x).begin(),(x).end()
#define arr(x) (x).rbegin(),(x).rend()
typedef long long ll;
typedef unsigned long long ull;
const ll inf=4e18;  
using graph = vector<vector<int> > ;
using vi=vector<int>;
using P= pair<ll,ll>;  
using pii=pair<int,int>;
using pll=pair<ll,ll>;
using vvi=vector<vi>;
using vvvi=vector<vvi>;
using vll=vector<ll>; 
using vvll=vector<vll>;
using vvvll=vector<vvll>;
using vp=vector<P>;
using vvp=vector<vp>;
using vvvp=vector<vvp>;
using vd=vector<double>;
using vvd =vector<vd>;
//using vs=vector<string>;
//string T="ABCDEFGHIJKLMNOPQRSTUVWXYZ";
//string S="abcdefghijklmnopqrstuvwxyz";
//g++ main.cpp -std=c++17 -I .  
//cout <<setprecision(20);
//cout << fixed << setprecision(10);
//cin.tie(0); ios::sync_with_stdio(false);

const double PI = acos(-1);
int vx[]={0,1,0,-1,-1,1,1,-1},vy[]={1,0,-1,0,1,1,-1,-1};
void putsYes(bool f){cout << (f?"Yes":"No") << endl;}
void putsYES(bool f){cout << (f?"YES":"NO") << endl;}
void putsFirst(bool f){cout << (f?"First":"Second") << endl;}
void debug(int test){cout << "TEST" << " " << test << endl;}
ll pow_pow(ll x,ll n,ll mod){
    if(n==0) return 1; 
    x%=mod;
    ll res=pow_pow(x*x%mod,n/2,mod);
    if(n&1)res=res*x%mod;
    return res;
}
ll gcdll(ll x,ll y){
    if(y==0)return x;
    return gcdll(y,x%y);
}
ll INFF=1000100100100100100;
ll lcmll(ll x,ll y){
    ll X=(x/gcdll(x,y)),Y=y;
    if(X<=INFF/Y)return X*Y;
    else return INFF;
}
template<class T> bool chmin(T& a, T b) {
    if (a > b) {
        a = b;
        return true;
    }
    else return false;
}
template<class T> bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    else return false;
}
struct edge{
  int to; ll cost;int id;
  edge(int to,ll cost,int id) : to(to),cost(cost),id(id) {}
};
using ve=vector<edge>;
using vve=vector<ve>;
int mod=998244353;
using mint=modint998244353;
using vm=vector<mint>;
using vvm=vector<vm>;
using vvvm=vector<vvm>;
constexpr int MAX = 10001000;
ll fact[MAX],finv[MAX],invv[MAX];
void initcomb(){
  fact[0]=fact[1]=1;
  finv[0]=finv[1]=1;
  invv[1]=1;
  for(int i=2;i<MAX;i++){
    fact[i]=fact[i-1]*i%mod;
    invv[i]=mod-invv[mod%i]*(mod/i)%mod;
    finv[i]=finv[i-1]*invv[i]%mod;
  }
}
ll comb(ll n,ll k){
  if(n<k) return 0;
  if(n<0||k<0) return 0;
  return fact[n]*(finv[k]*finv[n-k]%mod)%mod;
}
struct Compress{
   vll a;
   int cnt;
   Compress() :cnt(0) {}
   void add(ll x){a.push_back(x);}
   void init(){
       sort(all(a));
       a.erase(unique(all(a)),a.end());
       cnt=a.size();
   }
   ll to(ll x){
       int index=lower_bound(all(a),x)-a.begin();
       return index;
   } //変換先
   ll from(ll x){return a[x];}//逆引き
   int size(){return cnt;}
};
struct UnionFind { 
    vector<int> par, siz; 
    UnionFind(int n) : par(n, -1) , siz(n, 1) { } 
    int root(int x) { 
        if (par[x] == -1) return x;
        else return par[x] = root(par[x]);
    }
    bool issame(int x, int y) {
        return root(x) == root(y);
    }
    bool unite(int x, int y) {
        x = root(x), y = root(y);
        if (x == y) return false; 
        if (siz[x] < siz[y]) swap(x, y);
        par[y] = x;
        siz[x] += siz[y];
        return true;
    }
    int size(int x) {
        return siz[root(x)];
    }
};

vll anss; 
void solve(int test){
    ll n,m,k,l; cin >> n >> m >> k >> l;
    mint ans=0;
    repi(v1,l,m+1){
        ll rem=max(0ll,m*k-v1);
        mint tot=0;
        for(int i=0; i<=n-1; i++){
            mint now=1;
            now*=comb(n-1,i);
            now*=comb(rem-i*(m+1)+n-2,n-2);
            if(i%2)now*=-1;
            tot+=now;
        }
        mint tot2=0;
        for(int i=0; i<=n-1; i++){
            mint now=1;
            now*=comb(n-1,i);
            now*=comb(rem-i*(v1+1)+n-2,n-2);
            if(i%2)now*=-1;
            tot2+=now;
        }
       // cout << tot.val() <<" " << tot2.val() << endl;
        ans+=tot-tot2;
    }
    cout << ans.val() << endl;



}
//cat cf.cpp | pbcopy
//g++ cf.cpp -std=c++17 -I .  
int main(){cin.tie(0);ios::sync_with_stdio(false);
    initcomb();
    int t=1;//cin >>t;
    rep(test,t)solve(test);
    for(auto ans:anss){
        cout<< ans << endl;
    }
}