#pragma GCC optimize("Ofast")
#pragma GCC target("avx2,popcnt")

#include "bits/stdc++.h"

#define rep(i, n) for (int i = 0; i < (n); ++i)
#define rep1(i, n) for (int i = 1; i < (n); ++i)
#define rep1n(i, n) for (int i = 1; i <= (n); ++i)
#define repr(i, n) for (int i = (n) - 1; i >= 0; --i)
#define pb push_back
#define eb emplace_back
#define all(a) (a).begin(), (a).end()
#define rall(a) (a).rbegin(), (a).rend()
#define each(x, a) for (auto &x : a)
#define ar array
#define vec vector
#define range(i, n) rep(i, n)

using namespace std;

using ll = long long;
using ull = unsigned long long;
using ld = long double;
using str = string;
using pi = pair<int, int>;
using pl = pair<ll, ll>;

using vi = vector<int>;
using vl = vector<ll>;
using vpi = vector<pair<int, int>>;
using vvi = vector<vi>;

int Bit(int mask, int b) { return (mask >> b) & 1; }

template<class T>
bool ckmin(T &a, const T &b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}

template<class T>
bool ckmax(T &a, const T &b) {
    if (b > a) {
        a = b;
        return true;
    }
    return false;
}

// [l, r)
template<typename T, typename F>
T FindFirstTrue(T l, T r, const F &predicat) {
    --l;
    while (r - l > 1) {
        T mid = l + (r - l) / 2;
        if (predicat(mid)) {
            r = mid;
        } else {
            l = mid;
        }
    }
    return r;
}


template<typename T, typename F>
T FindLastFalse(T l, T r, const F &predicat) {
    return FindFirstTrue(l, r, predicat) - 1;
}

const ll INF = 2e18;
const int INFi = 1e9;
const int LG = 49;
const int N = 1e4 + 4;

template<int SZ>
struct hash_t {
    static bool initialized;
    static int MOD[SZ], BASE[SZ];
    static std::vector<int> POWER[SZ];

    static void initialize() {
        assert(!initialized);
        initialized = true;
        std::mt19937 rng(std::chrono::steady_clock::now().time_since_epoch().count());
        for (int i = 0; i < SZ; i++) {
            auto is_prime = [&](int x) {
                for (int i = 2; i * i <= x; i++)
                    if (x % i == 0)
                        return false;

                return true;
            };

            MOD[i] = int(8e5) + rng() % int(2e8 + 228);
            while (!is_prime(MOD[i]))
                MOD[i]++;

            BASE[i] = rng() % MOD[i];
            if (!(BASE[i] & 1))
                BASE[i]++;

            POWER[i].push_back(1);
        }
    }

    static void ensure(int n) {
        assert(initialized);
        if (int(POWER[0].size()) >= n)
            return;

        for (int i = 0; i < SZ; i++)
            for (int j = POWER[i].size(); j < n; j++)
                POWER[i].push_back(int64_t(POWER[i].back()) * BASE[i] % MOD[i]);
    }

    int length;
    std::array<int, SZ> h;

    hash_t() : length(0) {
        h.fill(0);
        if (!initialized)
            initialize();
    }

    template<typename T>
    hash_t(const T &value, int length = 1) : length(length) {
        if (!initialized)
            initialize();

        ensure(length);
        h.fill(0);
        for (int i = 0; i < SZ; i++)
            for (int j = 0; j < length; j++) {
                h[i] += int64_t(value) * POWER[i][j] % MOD[i];
                if (h[i] >= MOD[i])
                    h[i] -= MOD[i];
            }
    }

    hash_t<SZ> &operator+=(const hash_t<SZ> &x) {
        assert(initialized);
        ensure(x.length + 1);
        for (int i = 0; i < SZ; i++)
            h[i] = (int64_t(h[i]) * POWER[i][x.length] + x.h[i]) % MOD[i];

        length += x.length;
        return *this;
    }

    hash_t<SZ> &operator-=(const hash_t<SZ> &x) {
        assert(initialized);
        assert(x.length <= length);
        ensure(length - x.length + 1);
        for (int i = 0; i < SZ; i++) {
            h[i] -= int64_t(x.h[i]) * POWER[i][length - x.length] % MOD[i];
            if (h[i] < 0)
                h[i] += MOD[i];
        }
        length -= x.length;
        return *this;
    }

    bool operator==(const hash_t<SZ> &x) const {
        if (length != x.length)
            return false;

        return h == x.h;
    }

    bool operator<(const hash_t<SZ> &x) const {
        if (length != x.length)
            return length < x.length;

        return h < x.h;
    }

    friend hash_t<SZ> operator+(const hash_t<SZ> &left, const hash_t<SZ> &right) {
        return hash_t<SZ>(left) += right;
    }

    friend hash_t<SZ> operator-(const hash_t<SZ> &left, const hash_t<SZ> &right) {
        return hash_t<SZ>(left) -= right;
    }
};

template<int SZ> bool hash_t<SZ>::initialized = false;
template<int SZ> int hash_t<SZ>::MOD[SZ] = {};
template<int SZ> int hash_t<SZ>::BASE[SZ] = {};
template<int SZ> std::vector<int> hash_t<SZ>::POWER[SZ] = {};

using Hash = hash_t<2>;


struct SegTree {
    struct Node {
        Hash h_suf;
        Hash h_pref;

        ll mx;
        ll upd;

        void apply(ll x) {
            mx += x;
            upd += x;
        }

        void combine(const Node &a, const Node &b) {
            mx = max(a.mx, b.mx);
            h_suf = a.h_suf + b.h_suf;
            h_pref = b.h_pref + a.h_pref;
        }

        Node(ll v = 0) : h_suf(), h_pref(), mx(v), upd(0) {}
    };

    Node combine(const Node &a, const Node &b) {
        Node c;
        c.combine(a, b);
        return c;
    }

    vector<Node> t;
    int n;

    void build(int sz) {
        t.resize(sz * 4);
        n = sz;
    }

    void pull(int v) {
        t[v].combine(t[v << 1], t[v << 1 | 1]);
    }

    void push(int v) {
        if (!t[v].upd) return;
        t[v << 1].apply(t[v].upd);
        t[v << 1 | 1].apply(t[v].upd);
        t[v].upd = 0;
    }

    void Set(int v, int l, int r, int pos, ll x) {
        if (l > pos || r <= pos) return;
        if (l + 1 == r) {
            t[v].h_pref = t[v].h_suf = Hash(x);
            return;
        }
        push(v);
        Set(v << 1, l, (l + r) >> 1, pos, x);
        Set(v << 1 | 1, (l + r) >> 1, r, pos, x);
        pull(v);
    }

    void Set(int pos, ll x) {
        Set(1, 0, n, pos, x);
    }

    void Add(int v, int l, int r, int lq, int rq, ll x) {
        if (l >= rq || r <= lq) return;
        if (lq <= l && r <= rq) {
            t[v].apply(x);
            return;
        }
        push(v);
        Add(v << 1, l, (l + r) >> 1, lq, rq, x);
        Add(v << 1 | 1, (l + r) >> 1, r, lq, rq, x);
        pull(v);
    }

    void Add(int lq, int rq, ll x) {
        Add(1, 0, n, lq, rq, x);
    }

    Node Get(int v, int l, int r, int lq, int rq) {
        if (l >= rq || r <= lq) return Node(-INF);
        if (lq <= l && r <= rq) return t[v];
        push(v);
        return combine(Get(v << 1, l, (l + r) >> 1, lq, rq), Get(v << 1 | 1, (l + r) >> 1, r, lq, rq));
    }

    Node Get(int lq, int rq) {
        return Get(1, 0, n, lq, rq);
    }
};

void solve() {
    int n, q;
    ll k, b;
    cin >> n >> q >> k >> b;
    vl a(n);
    rep(i, n) {
        cin >> a[i];
        a[i] *= 2;
        a[i] -= 1ll * i * k;
    }
    b *= 2;
    SegTree st;
    st.build(n + 1);
    vl diff(n + 1, 0);
    auto update = [&](int lq, int rq, ll v) {
        st.Add(lq, rq, v);
        diff[lq] += v;
        st.Set(lq, diff[lq]);
        diff[rq] -= v;
        st.Set(rq, diff[rq]);
    };
    rep(i, n) update(i, i + 1, a[i]);

    rep(_, q) {
        int tp;
        cin >> tp;
        if (tp == 1) {
            int l, r;
            ll v;
            cin >> l >> r >> v;
            update(l - 1, r, v * 2);
            continue;
        }
        int i;
        cin >> i;
        i--;
        int ans = 0;
        if (i > 0 && i + 1 < n) {
            if (st.Get(i + 1, i + 2).mx - st.Get(i - 1, i).mx == b) {
                ans++;
            } else {
                assert(diff[i + 1] + diff[i] != b);
            }
        }
        for(int t = (1 << 20); t > 0; t /= 2) {
            if (!ans) break;
            if (i - ans - t < 0 || i + ans + t >= n) continue;
            auto lv = st.Get(i - ans - t + 1, i - ans + 1).h_suf;
            auto rv = st.Get(i + ans + 1, i + ans + t + 1).h_pref;
            bool ok = true;
            rep(j, 2) {
                if ((lv.h[j] + rv.h[j]) % hash_t<2>::MOD[j] != 0) {
                    ok = false;
                    break;
                }
            }
            if (!ok) continue;
            ans += t;
        }
        cout << ans << '\n';
    }
}

signed main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout << setprecision(12) << fixed;
    int t = 1;
//    cin >> t;
    rep(i, t) {
        solve();
    }
    return 0;
}

In file included from /usr/include/c++/13/string:43,
                 from /usr/include/c++/13/bitset:52,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:52,
                 from answer.code:4:
/usr/include/c++/13/bits/allocator.h: In destructor ‘constexpr std::_Vector_base<SegTree::Node, std::allocator<SegTree::Node> >::_Vector_impl::~_Vector_impl()’:
/usr/include/c++/13/bits/allocator.h:184:7: error: inlining failed in call to ‘always_inline’ ‘constexpr std::allocator< <template-parameter-1-1> >::~allocator() noexcept [with _Tp = SegTree::Node]’: target specific option mismatch
  184 |       ~allocator() _GLIBCXX_NOTHROW { }
      |       ^
In file included from /usr/include/c++/13/vector:66,
                 from /usr/include/c++/13/functional:64,
                 from /usr/include/x86_64-linux-gnu/c++/13/bits/stdc++.h:53:
/usr/include/c++/13/bits/stl_vector.h:133:14: note: called from here
  133 |       struct _Vector_impl
      |              ^~~~~~~~~~~~