#include <iostream>
#include <vector>
#include <string>
#include <fstream>
#include <algorithm>
#include <climits>
#include <cstdlib>
#include <cstdio>
#include <set>
#include <unordered_set>
#include <map>
#include <unordered_map>
#include <bitset>
#include <deque>
#include <queue>
#include <tuple>
#include <cmath>
#include <cctype>
#include <stack>
#include <cassert>
using namespace std;
using ll = long long;
struct vert {
int x, y, t;
};
bool cmp(const vert& a, const vert& b) {
if (a.x != b.x) return a.x < b.x;
return a.t < b.t;
}
int B, N, D, M;
int inp[3][100001];
vert verts[200001];
int bit1[150002]={};
void addv(int k, int v) {
for(; k <= 150000; k += k&-k) bit1[k] += v;
}
int sumr(int k) {
int s = 0;
for (; k >= 1; k -= k&-k) s += bit1[k];
return s;
}
int main() {
cin >> B >> N >> D >> M;
if (B==1) {
for (int i = 1; i <= N; i++) cin >> inp[0][i];
sort(inp[0]+1, inp[0]+1+N);
int idx = 1;
ll cnt = 0;
for (int i = 1; i <= N; i++) {
while (idx < N && inp[0][i]+D >= inp[0][idx+1]) idx++;
cnt += (idx-i);
}
cout << cnt << endl;
} else if (B==2) {
for (int i = 1; i <= N; i++) cin >> inp[0][i] >> inp[1][i];
for (int i = 1; i <= N; i++) {
verts[2*i-1] = {inp[0][i]-inp[1][i], inp[0][i]+inp[1][i], 0};
verts[2*i] = {inp[0][i]-inp[1][i]+D, inp[0][i]+inp[1][i], 1};
}
sort(verts+1, verts+1+2*N, cmp);
ll ans = 0;
for (int i = 1; i <= 2*N; i++) {
int y = verts[i].y;
if (verts[i].t == 0) {
int fy = max(2, y-D), sy = min(2*M, y+D);
ans += sumr(sy)-sumr(fy-1);
addv(y, 1);
} else {
addv(y, -1);
}
}
cout << ans << endl;
} else if (B==3) {
for (int i = 1; i <= N; i++) cin >> inp[0][i] >> inp[1][i] >> inp[2][i];
}
return 0;
}
