#include <iostream>
#include <algorithm>
using namespace std;
constexpr int N = 1e5 + 5;
namespace subtask1 {
int points[N];
void solve(int n, int D) {
for (int i = 0; i < n; i++) {
cin >> points[i];
}
sort(points, points + n);
long long res = 0;
int j = 0;
for (int i = 0; i < n; i++) {
while (points[i] - points[j] > D) j++;
res += i - j;
}
cout << res;
}
}
namespace subtask2 {
struct Point {
int x, y;
auto operator<=>(const Point &) const = default;
} points[N];
constexpr int M = 75000 + 5;
int m;
int tree[M * 2];
template <int w>
void update(int i) {
for (; i <= m; i += i & -i) {
tree[i] += w;
}
}
int query(int i) {
int s = 0;
for (; i; i &= i - 1) {
s += tree[i];
}
return s;
}
void solve(int n, int D, int magnitude) {
m = magnitude * 2 - 1;
for (int i = 0; i < n; i++) {
int x, y;
cin >> x >> y;
points[i] = {x + y - 1, x - y + magnitude};
}
sort(points, points + n);
long long res = 0;
int j = 0;
for (int i = 0; i < n; i++) {
auto [x, y] = points[i];
while (x - points[j].x > D) {
update<-1>(points[j++].y);
}
res += query(min(m, y + D)) - query(max(y - D - 1, 0));
update<1>(y);
}
cout << res;
}
}
namespace subtask3 {
constexpr int M = 75;
int m;
struct {
int tree[2 * M][2 * M];
template <int w>
void update(int x, int y) {
tree[x][y] += w;
}
void build() {
for (int x = 1; x <= m; x++) {
for (int y = 1; y <= m; y++)
tree[x][y] += tree[x - 1][y];
}
for (int x = 1; x <= m; x++) {
for (int y = 1; y <= m; y++)
tree[x][y] += tree[x][y - 1];
}
}
int query(int x, int y) {
return tree[x][y];
}
} trees[M + 1];
struct Point {
int x, y, z;
} points[N];
void solve(int n, int D, int magnitude) {
m = magnitude * 2 - 1;
for (int i = 0; i < n; i++) {
int x, y, z;
cin >> x >> y >> z;
points[i] = {z, x + y - 1, x - y + magnitude};
trees[z].update<1>(points[i].y, points[i].z);
}
for (int x = 1; x <= m; x++) {
trees[x].build();
}
long long res = 0;
for (int i = 0; i < n; i++) {
auto [x, y, z] = points[i];
for (int xp = 1; xp <= m; xp++) {
int d = D - abs(xp - x);
if (d < 0) continue;
int yl = max(0, y - d - 1);
int yr = min(m, y + d);
int zl = max(0, z - d - 1);
int zr = min(m, z + d);
res += trees[xp].query(yr, zr) - trees[xp].query(yr, zl) - trees[xp].query(yl, zr) + trees[xp].query(yl, zl);
}
}
cout << (res - n) / 2;
}
}
signed main()
{
ios::sync_with_stdio(false);
cin.tie(NULL);
cout.tie(NULL);
// freopen("input.txt", "r", stdin);
int dimension, n, D, magnitude;
cin >> dimension >> n >> D >> magnitude;
if (dimension == 1) {
subtask1::solve(n, D);
return 0;
}
if (dimension == 2) {
subtask2::solve(n, D, magnitude);
return 0;
}
subtask3::solve(n, D, magnitude);
return 0;
}
