Apartments

#include <bits/stdc++.h>
using namespace std;
using ll = long long;

const int N = 2e5+1;
int A[N], B[N];
int n, m, k;

int main() {
	cin >> n >> m >> k;
	for (int i = 0; i < n; ++i) {
		cin >> A[i];
	}
	for (int i = 0; i < m; ++i) {
		cin >> B[i];
	}
	sort(A,A+n);
	sort(B,B+m);
	int j = 0, ans = 0;
	for (int i = 0; i < n; ++i) {
		while (j < m && B[j] + k < A[i]) {
			++j;
		}
		if (j == m) break;
		if (B[j] - k <= A[i]) {
			++ans;
			++j;
		}
	}
	cout << ans;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: ACCEPTED

Test 13

Verdict: ACCEPTED

Test 14

Verdict: ACCEPTED

Test 15

Verdict: ACCEPTED

Test 16

Verdict: ACCEPTED

Test 17

Verdict: ACCEPTED

Test 18

Verdict: ACCEPTED

Test 19

Verdict: ACCEPTED