Apartments

#include <iostream>
#include <algorithm>
#include <vector>

using namespace std;

int main() {
    ios::sync_with_stdio(0);
    cin.tie(nullptr);
    // freopen("input.txt", "r", stdin);
    int n, m, k;
    cin >> n >> m >> k;
    vector<int> prefs(n);
    vector<int> aparts(m);

    for (int i = 0; i < n; i++) {
        cin >> prefs[i];
    }
    for (int i = 0; i < m; i++) {
        cin >> aparts[i];
    }
    sort(prefs.begin(), prefs.end());
    sort(aparts.begin(), aparts.end());
    int ans = 0;
    int a = 0; int b = 0;
    while (a < n && b < m) {
        if (prefs[a] < aparts[b] - k) {
            a++;
        } else if (prefs[a] > aparts[b] + k) {
            b++;
        } else {
            ans++;
            a++;
            b++;
        }
    }
    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