#include <bits/stdc++.h>
using namespace std;

#define NDEBUG
#include <cassert>


typedef long long ll;
typedef long double Double;
typedef unsigned long long ull;
typedef pair<int,int> ii;
typedef pair<ll,ll> llll;
typedef pair<double,double> dd;

typedef vector<int> vi;
typedef vector<vector<int>> vvi;
typedef vector<ii> vii;
typedef vector<vector<ii>> vvii;
typedef vector<ll> vll;
typedef vector<vector<ll>> vvll;
typedef vector<llll> vllll;
typedef vector<bool> vb;
typedef vector<string> vs;
typedef vector<double> vd;
typedef vector<long double> vD;

#define sz(a)  int((a).size())
#define pb  push_back
#define eb  emplace_back
#define FOR(var,from,to) for(int var=(from);var<=(to);++var)
#define rep(var,n)  for(int var=0;var<(n);++var)
#define rep1(var,n)  for(int var=1;var<=(n);++var)
#define repC2(vari,varj,n)  for(int vari=0;vari<(n)-1;++vari)for(int varj=vari+1;varj<(n);++varj)
#define repC3(vari,varj,vark,n)  for(int vari=0;vari<(n)-2;++vari)for(int varj=vari+1;varj<(n)-1;++varj)for(int vark=varj+1;vark<(n);++vark)
#define ALL(c)  (c).begin(),(c).end()
#define RALL(c)  (c).rbegin(),(c).rend()
#define tr(i,c)  for(auto i=(c).begin(); i!=(c).end(); ++i)
#define found(s,e)  ((s).find(e)!=(s).end())
#define mset(arr,val)  memset(arr,val,sizeof(arr))
#define mid(x,y) ((x)+((y)-(x))/2)
#define IN(x,a,b) ((a)<=(x)&&(x)<=(b))
#define cons make_pair
#define clamp(v,lo,hi) min(max(v,lo),hi)
#define ABS(x) max((x),-(x))

template<typename T1, typename T2> inline void amin(T1 & a, T2 const & b) { if (a>b) a=b; }
template<typename T1, typename T2> inline void amax(T1 & a, T2 const & b) { if (a<b) a=b; }
template<typename X, typename T> auto vectors(X x, T a) { return vector<T>(x, a); }
template<typename X, typename Y, typename Z, typename... Zs> auto vectors(X x, Y y, Z z, Zs... zs) { auto cont = vectors(y, z, zs...); return vector<decltype(cont)>(x, cont); }

inline ll square(ll x) { return x * x; }
inline ll gcd(ll a, ll b) { while(a) swap(a, b%=a); return b; }
inline ll lcm(ll a, ll b) { return a/gcd(a,b)*b; }
template <typename T>
inline T mod(T a, T b) { return ((a % b) + b) % b; }

template <typename T>
int find_left(vector<T>& v, T elem) {
    return (int)(upper_bound(v.begin(), v.end(), elem) - v.begin()) - 1;
}
template <typename T>
int find_right(vector<T>& v, T elem) {
    return (int)(lower_bound(v.begin(), v.end(), elem) - v.begin());
}

const ll MOD=998244353LL;

inline ll ADD(ll x, ll y) { return (x+y) % MOD; }
inline ll SUB(ll x, ll y) { return (x-y+MOD) % MOD; }
inline ll MUL(ll x, ll y) { return x*y % MOD; }
inline ll POW(ll x, ll e) { ll v=1; for(; e; x=MUL(x,x), e>>=1) if (e&1) v = MUL(v,x); return v; }
inline ll INV(ll y) { /*assert(y%MOD!=0);*/ return POW(y, MOD-2); }
inline ll DIV(ll x, ll y) { return MUL(x, INV(y)); }

using T = map<int,ll>;

class SegmentTree {
public:
    int bit_, N;
    vector<T> buf_;

    SegmentTree(int size) {
        N = 1;
        bit_ = 0;
        while (N < size) {
            N *= 2;
            ++bit_;
        }

        buf_.resize(N*2);
    }

    T merge(T& a, T& b) {
        if (a.empty()) a[0]=1;
        if (b.empty()) b[0]=1;

        T c;
        for (auto& p: a){
            for (auto& q: b){
                int ix = p.first + q.first;
                if (ix <= 3000) {
                    c[ix] += MUL(p.second, q.second);
                }
            }
        }
        return c;
    }

    void update(int i, T& x) {
        i = N + i - 1;

        if (merge(buf_[i], x) != x) return;

        buf_[i] = x;
        while (i > 0) {
			i = (i - 1) / 2;
			buf_[i] = merge(buf_[i*2+1], buf_[i*2+2]);
        }
    }

    T query(int lo, int hi) {
        return query(lo, hi, 0, 0, N);
    }
    T query(int a, int b, int k, int l, int r) {
        if (r <= a || b <= l) return T();

        if (a <= l && r <= b) {
            return buf_[k];
        } else {
			T lv = query(a, b, 2*k+1, l, (l+r)/2);
			T rb = query(a, b, 2*k+2, (l+r)/2, r);
			return merge(lv, rb);
        }
    }

    void dump() {
    }
};


ll solve(int N, int S, vi& a) {
    SegmentTree st(N);

    rep(i,N){
        T ai;
        ai[0] = ai[a[i]] = 1;
        st.update(i, ai);
    }

    ll total = 0;
    rep(l,N){
        if (a[l] != S) continue;


        int left = l, right = N-left-1;

        ll cnt = 1;
        ll mag = MUL(left+1, right+1);
        total = ADD(total, MUL(cnt, mag));
    }
    repC2(l,r,N){
        int rem = S - a[l] - a[r];
        if (rem < 0) continue;
        int left = l, right = N-r-1;
        ll cnt = 0;
        if (l+1 == r) {
            cnt = (rem == 0)? 1 : 0;
        } else {
            T pat = st.query(l+1, r);
            cnt = pat[rem];
            if (cnt == 0) continue;
        }
        ll mag = MUL(left+1, right+1);
        total = ADD(total, MUL(cnt, mag));
    }
    return total;
}

int main() {

    int N, S; cin >> N >> S;
    vi a(N);
    rep(i,N) cin >> a[i];
    cout << solve(N,S,a) << endl;
    return 0;
}
