#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef pair <ll,ll> P;
#define _for(x,y,z) for (int x(y),_(z); x<=_; ++x)
#define _rep(x,y,z) for (int x(y),_(z); x>=_; --x)
inline ll read(){ ll x; scanf("%lld",&x); return x; }
inline void _init(){
	#ifdef LOCAL
		assert(freopen("test.in", "r", stdin));
		assert(freopen("test.out", "w", stdout));
	#endif
	ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
}

const int N = 2e5 + 5;

const ll base = 2131073233ll;
const ll mod = (ll)1e18 + 3;
ll pw[N], qz[N];
ll n, q, k, B, a[N], b[N], c[N];
struct Hsh{
	ll hsh, sz;
	Hsh(ll a=0, ll b=0){ hsh=a, sz=b; }
};
Hsh operator+ (Hsh A, Hsh B){
	return Hsh((A.hsh+(__int128)pw[A.sz]*B.hsh)%mod, A.sz+B.sz);
}

struct Seg1{
	Hsh t[4*N]; ll tag[4*N],len[4*N];
	void pushup(ll pos){
		t[pos]=t[pos<<1]+t[pos<<1|1];
	}
	void upd(ll pos,ll v){
		t[pos].hsh = (t[pos].hsh + (__int128)(v + mod) * qz[t[pos].sz-1]) % mod;
		tag[pos] = (tag[pos] + v) % mod;
	}
	void pushdown(ll pos){
		if(tag[pos]){
			upd(pos<<1, tag[pos]);
			upd(pos<<1|1, tag[pos]);
			tag[pos]=0;
		}
	}
	void build(ll l,ll r,ll pos){
		if(l==r){
			t[pos] = Hsh(b[l]<0?mod+b[l]:b[l], 1);
			// cout<<"at "<<l<<" is "<<(b[l]<0?mod+b[l]:b[l])<<endl;
			return;
		}
		ll mid=(l+r)>>1;
		if(l<=mid) build(l,mid,pos<<1);
		if(mid<r) build(mid+1,r,pos<<1|1);
		pushup(pos);
	}
	void update(ll l,ll r,ll ql,ll qr,ll v,ll pos){
		if(ql<=l && r<=qr){
			upd(pos, v);
			return;
		}
		ll mid=(l+r)>>1;
		pushdown(pos);
		if(ql<=mid) update(l,mid,ql,qr,v,pos<<1);
		if(mid<qr)  update(mid+1,r,ql,qr,v,pos<<1|1);
		pushup(pos);
	}
	Hsh ans;
	void query(ll l,ll r,ll ql,ll qr,ll pos){
		if(ql>qr) return;
		if(ql<=l && r<=qr) {
			ans = ans + t[pos];
			return;
		}
		ll mid=(l+r)>>1;
		pushdown(pos);
		if(ql<=mid) query(l,mid,ql,qr,pos<<1);
		if(mid<qr)  query(mid+1,r,ql,qr,pos<<1|1);
		pushup(pos);
	}
	ll hash(ll l,ll r,ll op=0){
		ans=Hsh(0,0);
		query(1,n,l,r,1);
		// if(op) cout<<"between "<<l<<" "<<r<<" hash = "<<ans.hsh<<endl;
		return ans.hsh;
	}
}S;


struct Seg2{
	Hsh t[4*N]; ll tag[4*N],len[4*N];
	void pushup(ll pos){
		t[pos]=t[pos<<1|1]+t[pos<<1];
	}
	void upd(ll pos,ll v){
		t[pos].hsh = (t[pos].hsh + (__int128)(v + mod) * qz[t[pos].sz-1]) % mod;
		tag[pos] = (tag[pos] + v) % mod;
	}
	void pushdown(ll pos){
		if(tag[pos]){
			upd(pos<<1, tag[pos]);
			upd(pos<<1|1, tag[pos]);
			tag[pos]=0;
		}
	}
	void build(ll l,ll r,ll pos){
		if(l==r){
			t[pos] = Hsh(b[l]<0?mod+b[l]:b[l], 1);
			// cout<<"at "<<l<<" is "<<(b[l]<0?mod+b[l]:b[l])<<endl;
			return;
		}
		ll mid=(l+r)>>1;
		if(l<=mid) build(l,mid,pos<<1);
		if(mid<r) build(mid+1,r,pos<<1|1);
		pushup(pos);
	}
	void update(ll l,ll r,ll ql,ll qr,ll v,ll pos){
		if(ql<=l && r<=qr){
			upd(pos, v);
			return;
		}
		ll mid=(l+r)>>1;
		pushdown(pos);
		if(ql<=mid) update(l,mid,ql,qr,v,pos<<1);
		if(mid<qr)  update(mid+1,r,ql,qr,v,pos<<1|1);
		pushup(pos);
	}
	Hsh ans;
	void query(ll l,ll r,ll ql,ll qr,ll pos){
		if(ql>qr) return;
		if(ql<=l && r<=qr) {
			ans = t[pos] + ans;
			return;
		}
		ll mid=(l+r)>>1;
		pushdown(pos);
		if(ql<=mid) query(l,mid,ql,qr,pos<<1);
		if(mid<qr)  query(mid+1,r,ql,qr,pos<<1|1);
		pushup(pos);
	}
	ll hash(ll l,ll r,ll op=0){
		ans=Hsh(0,0);
		query(1,n,l,r,1);
		// if(op) cout<<"between "<<l<<" "<<r<<" hash = "<<ans.hsh<<endl;
		return ans.hsh;
	}
}T;

void init() {
	pw[0] = qz[0] = 1;
	for(ll i=1;i<N;i++) pw[i]=(__int128)pw[i-1]*base%mod;
	for(ll i=1;i<N;i++) qz[i]=(qz[i-1]+pw[i])%mod;
}
void procedure() {
	n=read(), q=read(), k=read(), B=2*read();
	for(ll i=1;i<=n;i++){
		a[i]=read();
		b[i]=2*a[i]-i*k+1e9;
	}

	// for(ll i=1;i<=n;i++) cout<<b[i]<<" "; cout<<endl;
	S.build(1,n,1); T.build(1,n,1);
	while(q--){
		ll op=read();
		if(op==1){
			ll l=read(), r=read(), v=read()*2;
			S.update(1,n,l,r,v,1); T.update(1,n,l,r,v,1);
		}else{
			ll x=read();
			ll l=1, r=min(x-1, n-x), ans=0;
			S.update(1,n,1,x-1,B,1);
			while(l<=r){
				ll mid=(l+r)>>1;
				if(S.hash(x-mid,x-1,1) == T.hash(x+1,x+mid,1)){
					ans=mid; l=mid+1;
				}else r=mid-1;
			}
			S.update(1,n,1,x-1,-B,1);
			// cout<<ans<<endl;
			printf("%lld\n", ans);
		}

		// cout<<"now "; for(ll i=1;i<=n;i++) cout<<S.hash(i,i)<<" "; cout<<endl;
	}
}

int main() {
	_init(), init();
	int T=1;
	while(T--) procedure();
	return 0;
}