Apartments

#include <bits/stdc++.h>

using namespace std;

//Definitions for quicker writing
#define REP(i,a,b) for (int i = a; i < b; i++)

//Typedefs for quicker writing
typedef long long ll;
typedef vector<int> vi;
typedef pair<int,int> pi;

int main() {
	//IO optimization
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	//Input definition
	int n,m,k;
	
	//Read In
	cin >> n >> m >> k;

	vi wishes;
	vi apps;

	REP(i,0,n){
		int wish;
		cin >> wish;
		wishes.push_back(wish);
	}

	REP(i,0,m){
		int app;
		cin >> app;
		apps.push_back(app);
	}

	//Main part
	
	sort(wishes.begin(), wishes.end());
	sort(apps.begin(), apps.end());
	
	int appcount = 0;

	REP(i,0,n){
		auto it_lb = lower_bound(apps.begin(), apps.end(), wishes[i]); 
		auto id_lb = it_lb - apps.begin();
		if(id_lb < m && abs(apps[id_lb]-wishes[i]) <= k){
			apps.erase(it_lb);
			appcount++;
		}
		else{
			auto it_ub = upper_bound(apps.begin(), apps.end(), wishes[i]);
			auto id_ub = it_ub - apps.begin();
			if(id_ub < m && abs(apps[id_ub]-wishes[i]) <= k){
				apps.erase(it_ub);
				appcount++;
			}

		}
	}
	

	//Write out
	cout << appcount << "\n";
		
	//Return
	return 0;

}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: RUNTIME ERROR

double free or corruption (out)

Test 3

Verdict: ACCEPTED

Test 4

Verdict: RUNTIME ERROR

double free or corruption (out)

Test 5

Verdict: TIME LIMIT EXCEEDED

Test 6

Verdict: TIME LIMIT EXCEEDED

Test 7

Verdict: TIME LIMIT EXCEEDED

Test 8

Verdict: TIME LIMIT EXCEEDED

Test 9

Verdict: ACCEPTED

Test 10

Verdict: ACCEPTED

Test 11

Verdict: ACCEPTED

Test 12

Verdict: RUNTIME ERROR

Test 13

Verdict: ACCEPTED

Test 14

Verdict: WRONG ANSWER

Test 15

Verdict: WRONG ANSWER

Test 16

Verdict: TIME LIMIT EXCEEDED

Test 17

Verdict: RUNTIME ERROR

free(): invalid pointer

Test 18

Verdict: ACCEPTED

Test 19

Verdict: RUNTIME ERROR

double free or corruption (out)