#include <bits/stdc++.h>
#define pb emplace_back
#define SZ(x) ((int)x.size())
#define fi first
#define se second
#define FOR(i, a, b) for (int i = a, _b = b; i <= _b; ++i)
#define FORD(i, a, b) for (int i = a, _b = b; i >= _b; --i)
#define FORLL(i, a, b) for (ll i = a, _b = b; i <= _b; ++i)
#define FORDLL(i, a, b) for (ll i = a, _b = b; i >= _b; --i)
#define all(x) x.begin(), x.end()
#define uni(x) sort(all(x)), x.erase(unique(all(x)), x.end())
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define dbg(...) debug(#__VA_ARGS__, __VA_ARGS__)
template<typename T>
void __prine_one(const char *&s, const T &x)
{
while (*s == ' ') ++s;
const char *p = s;
int bal = 0;
while (*s)
{
if (*s == '(') ++bal;
else if (*s == ')') --bal;
else if (*s == ',' && bal == 0) break;
++s;
}
cerr.write(p, s - p) << " = " << x;
if (*s == ',')
{
cerr << " , ";
++s;
}
}
template<typename... Args>
void debug(const char *s, Args... args)
{
cerr << "[ ";
int dummy[] = {0, (__prine_one(s, args), 0)...};
(void)dummy;
cerr << " ]\n\n";
}
template<class X>
bool maximize(X &a, const X &b)
{
if (b > a)
{
a = b;
return true;
}
return false;
}
template<class X>
bool minimize(X &a, const X &b)
{
if (b < a)
{
a = b;
return true;
}
return false;
}
#define inline inline __attribute__ ((always_inline))
// --------------------------------------------------------------------------------------------
constexpr int maxn = 1e5 + 3;
int n, B, M;
ll D;
// --------------------------------------------------------------------------------------------
void readInput()
{
cin >> B >> n >> D >> M;
}
namespace sub1
{
int a[maxn];
ll res;
void solve()
{
FOR(i, 1, n)
cin >> a[i];
sort(a + 1, a + n + 1);
int j = 1;
FOR(i, 1, n)
{
while (j <= i && a[i] - a[j] > D)
++j;
res += i - j;
}
cout << res;
}
}
namespace sub2
{
ll res;
struct Point
{
ll x, y;
bool operator < (const Point &other) const
{
if (x != other.x) return x < other.x;
return y < other.y;
}
} a[maxn];
vector<int> idsy;
int lower(ll x) {return lower_bound(all(idsy), x) - idsy.begin() + 1;}
int upper(ll x) {return upper_bound(all(idsy), x) - idsy.begin() + 1;}
struct FenTree
{
vector<int> fw;
void init(int n)
{
fw.assign(n + 3, 0);
}
void upd(int pos, int val)
{
for (; pos <= SZ(fw); pos += pos & -pos)
fw[pos] += val;
}
int get(int pos)
{
int res = 0;
for (; pos; pos &= pos - 1)
res += fw[pos];
return res;
}
int get(int l, int r)
{
if (l > r) return 0;
return get(r) - get(l - 1);
}
} fw;
void solve()
{
FOR(i, 1, n)
{
ll curx, cury; cin >> curx >> cury;
a[i].x = curx + cury;
a[i].y = curx - cury;
idsy.push_back(a[i].y);
}
sort(a + 1, a + n + 1);
uni(idsy);
fw.init(SZ(idsy));
int j = 1;
FOR(i, 1, n)
{
while (a[i].x - a[j].x > D)
{
fw.upd(lower(a[j].y), -1);
++j;
}
res += fw.get(lower(a[i].y - D), upper(a[i].y + D) - 1);
fw.upd(lower(a[i].y), 1);
}
cout << res;
}
}
namespace sub3
{
ll res;
struct Point
{
ll x, y, z, t;
int idy, idz, idt;
} a[maxn];
vector<int> yids, zids, tids;
inline int lower(vector<int> &ids, ll x) { return lower_bound(all(ids), x) - ids.begin() + 1; }
inline int upper(vector<int> &ids, ll x) { return upper_bound(all(ids), x) - ids.begin() + 1; }
struct FenTree2D
{
vector<vector<int>> ids;
vector<vector<int>> fw;
inline void init(int n)
{
ids.resize(n + 3);
fw.resize(n + 3);
FOR(i, 1, n)
ids[i].push_back(int(-1e9));
}
inline void upd(int x, int y, int val)
{
for (int curx = x; curx <= SZ(zids); curx += curx & -curx)
for (int cury = upper(ids[curx], y) - 1; cury < SZ(fw[curx]); cury += cury & -cury)
fw[curx][cury] += val;
}
inline int get(int x, int y)
{
int res = 0;
for (int curx = x; curx; curx &= curx - 1)
for (int cury = upper(ids[curx], y) - 1; cury; cury &= cury - 1)
res += fw[curx][cury];
return res;
}
inline int get(int x, int y, int u, int v)
{
return get(u, v) - get(u, y - 1) - get(x - 1, v) + get(x - 1, y - 1);
}
} fw[1005];
inline void updPoint(Point &a, int val)
{
fw[a.idy].upd(a.idz, a.idt, val);
}
void solve()
{
FOR(i, 1, n)
{
ll x, y, z; cin >> x >> y >> z;
a[i].x = x + y + z;
a[i].y = x + y - z;
a[i].z = x - y + z;
a[i].t = x - y - z;
yids.push_back(a[i].y);
zids.push_back(a[i].z);
tids.push_back(a[i].t);
}
sort(a + 1, a + n + 1, [&](const Point &a, const Point &b)
{
if (a.x != b.x) return a.x < b.x;
if (a.y != b.y) return a.y < b.y;
if (a.z != b.z) return a.z < b.z;
return a.t < b.t;
});
uni(yids);
uni(zids);
uni(tids);
FOR(i, 1, n)
{
a[i].idy = lower(yids, a[i].y);
a[i].idz = lower(zids, a[i].z);
a[i].idt = lower(tids, a[i].t);
}
fw[1].init(SZ(zids));
FOR(i, 1, n)
{
for (int id = a[i].idz; id <= SZ(zids); id += id & -id)
{
// dbg(id, a[i].idt);
fw[1].ids[id].push_back(a[i].idt);
}
}
FOR(i, 1, SZ(zids))
{
uni(fw[1].ids[i]);
fw[1].ids[i].push_back(1e9);
fw[1].ids[i].push_back(1e9);
fw[1].fw[i].assign(SZ(fw[1].ids[i]), 0);
}
FOR(i, 2, SZ(yids))
fw[i] = fw[i - 1];
int j = 1;
FOR(i, 1, n)
{
while (a[i].x - a[j].x > D)
{
updPoint(a[j], -1);
++j;
}
updPoint(a[i], 1);
}
cout << res;
}
}
void solve()
{
if (B == 1) return sub1 :: solve(), void();
if (B == 2) return sub2 :: solve(), void();
sub3 :: solve();
}
signed main()
{
ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL);
#define TASK "TEST"
if (fopen(TASK".INP", "r"))
{
freopen(TASK".INP", "r", stdin);
freopen(TASK".OUT", "w", stdout);
}
readInput();
solve();
return 0;
}
