Järjestäminen

input/code.cpp: In function 'bool explore()':
input/code.cpp:30:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < current.size() - 3; i++) {
                  ~~^~~~~~~~~~~~~~~~~~~~
input/code.cpp:31:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for (int j = i + 2; j < current.size() - 1; j++) {
                       ~~^~~~~~~~~~~~~~~~~~~~

#include <bits/stdc++.h>
#include <unordered_map>
#define ll long long
#define ull unsigned long long

using namespace std;

unordered_map<string, bool> m;
unordered_map<string, bool> m2;

string current = "";
string target = "";

void reset() {
	// memset(arr, 0, sizeof(arr));
	m = {};
	//m2 = {};
	current = "";
	target = "";
}

bool explore() {
	//cout << current << ",\n";
	if (current == target) return true;
	if (m2[current]) return true;
	if (m[current]) return false;

	m[current] = true;

	for (int i = 0; i < current.size() - 3; i++) {
		for (int j = i + 2; j < current.size() - 1; j++) {
			swap(current[i], current[j]);
			swap(current[i+1], current[j+1]);
			if (explore()) return true;

			swap(current[i], current[j]);
			swap(current[i + 1], current[j + 1]);
		}
	}

	return false;
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);

//	istringstream cin(R"(3
//2
//1 2
//5
//2 3 5 1 4
//7
//5 3 4 2 1 6 7)");
	

	ll t; cin >> t;

	/////
	//current = "12345678";
	//target = "";
	//explore();
	//for (auto x : m) m2[x.first] = true;
	//reset();
	/////
	//current = "1234567";
	//target = "";
	//explore();
	//for (auto x : m) m2[x.first] = true;
	//reset();
	/////
	//current = "123456";
	//target = "";
	//explore();
	//for (auto x : m) m2[x.first] = true;
	//reset();
	/////
	//current = "12345";
	//target = "";
	//explore();
	//for (auto x : m) m2[x.first] = true;
	//reset();
	/////
	//current = "1234";
	//target = "";
	//explore();
	//for (auto x : m) m2[x.first] = true;
	//reset();



	for (int i = 0; i < t; i++) {
		char n; cin >> n;

		reset();

		for (int j = '1'; j <= n; j++) {
			char x; cin >> x;
			current += x;
			target += j;
		}

		if (explore()) {
			cout << "YES" << "\n";
			for (auto x : m) {
				m2[x.first] = true;
			}
		} else {
			cout << "NO" << "\n";
		}
	}

	//cout << x;

}

Test 1

Group: 1, 2

Verdict: TIME LIMIT EXCEEDED

Test 2

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: TIME LIMIT EXCEEDED