//#define _GLIBCXX_DEBUG #include using namespace std; #define rep(i, n) for(int i=0; i; using vs = vector; using vi = vector; using vvi = vector; template using PQ = priority_queue; template using PQG = priority_queue, greater>; const int INF = 0xccccccc; const ll LINF = 0xcccccccccccccccLL; template inline bool chmax(T1 &a, T2 b) {return a < b && (a = b, true);} template inline bool chmin(T1 &a, T2 b) {return a > b && (a = b, true);} template istream &operator>>(istream &is, pair &p) { return is >> p.first >> p.second;} template ostream &operator<<(ostream &os, const pair &p) { return os << p.first << ' ' << p.second;} const unsigned int mod = 1000000007; //const unsigned int mod = 998244353; struct mint { unsigned int x; mint():x(0) {} mint(int64_t x_) { int64_t v = int64_t(x_ % mod); if(v < 0) v += mod; x = (unsigned int)v; } static mint row(int v) { mint v_; v_.x = v; return v_; } mint operator-() const { return row(x?mod-x:0);} mint& operator+=(const mint a) { if ((x += a.x) >= mod) x -= mod; return *this; } mint& operator-=(const mint a) { if ((x += mod-a.x) >= mod) x -= mod; return *this; } mint& operator*=(const mint a) { uint64_t z = x; z *= a.x; x = (unsigned int)(z % mod); return *this; } mint operator+(const mint a) const { return mint(*this) += a;} mint operator-(const mint a) const { return mint(*this) -= a;} mint operator*(const mint a) const { return mint(*this) *= a;} friend bool operator==(const mint &a, const mint &b) {return a.x == b.x;} friend bool operator!=(const mint &a, const mint &b) {return a.x != b.x;} mint &operator++() { x++; if(x == mod) x = 0; return *this; } mint &operator--() { if(x == 0) x = mod; x--; return *this; } mint operator++(int) { mint result = *this; ++*this; return result; } mint operator--(int) { mint result = *this; --*this; return result; } mint pow(int64_t t) const { mint x_ = *this, r = 1; while(t) { if(t&1) r *= x_; x_ *= x_; t >>= 1; } return r; } //for prime mod mint inv() const { return pow(mod-2);} mint& operator/=(const mint a) { return *this *= a.inv();} mint operator/(const mint a) {return mint(*this) /= a;} }; istream& operator>>(istream& is, mint& a) { return is >> a.x;} ostream& operator<<(ostream& os, const mint& a) { return os << a.x;} string to_string(mint a) { return to_string(a.x); } struct combination { vector frac, ifrac; combination(int n):frac(n+1), ifrac(n+1) { assert((unsigned int)(n) < mod); frac[0] = 1; for (int i = 1; i <= n; ++i) frac[i] = frac[i-1]*i; ifrac[n] = frac[n].inv(); for (int i = n; i >= 1; --i) ifrac[i-1] = ifrac[i]*i; } mint operator()(int n, int k) { if (k < 0 || k > n) return 0; return frac[n]*ifrac[k]*ifrac[n-k]; } } c(100000); #define N 42 #define M 20010 //head mint dp[N][N][M]; int main() { ios::sync_with_stdio(false); cin.tie(0); int n, mp, mq, l; cin >> n >> mp >> mq >> l; vi s(n); rep(i, n) cin >> s[i]; dp[0][0][0] = 1; rep(i, n) { rep(j, i+2) { rep(k, mq+1) { if(j and k) { dp[i+1][j][k] += dp[i+1][j][k-1]+dp[i][j-1][k-1]; if(k > s[i]) dp[i+1][j][k] -= dp[i][j-1][k-s[i]-1]; } } rep(k, mq+1) { dp[i+1][j][k] += dp[i][j][k]; } } } mint ans; rep(j, n+1) { rep(k, mq+1) { ans += dp[n][j][k]*c(mp-l*j+k+n-1, n-1); } } cout << ans << endl; }