oj.uz

Submission #707946

# Submission time Handle Problem Language Result Execution time Memory
707946 2023-03-10T14:57:03 Z josanneo22 Xor Sort (eJOI20_xorsort) C++17
60 / 100
 193 ms 1924 KB 
#include <bits/stdc++.h>
#include <unordered_map>
#define ll long long
#define ld long double
#define pll pair <ll,ll>
#define F first
#define S second
#define pb push_back
#define IOS ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0)
using namespace std;

int n, type;
vector <ll> a;
vector <pll> ans;
void solve1() {
	int mn = 2e9;
	vector <pll> ans2;
	for (int i = 0; i < n - 1; i++)
		a[i] ^= a[i + 1];
	for (int j = 0; j < n; j++) {
		vector<ll> aa;
		aa = a;
		for (int i = 0; i < n; i++)
			if (i != j) a[i] ^= a[j];
		ans.clear();
		vector<ll> ab;
		ab = aa;
		for (int i = 0; i < n - 1; i++)
			ans.pb({ i + 1,i + 2 });
		for (int i = j + 1; i < n; i++)
		{
			ans.pb({ i + 1,i });
			ab[i] ^= ab[i - 1];
		}
		for (int i = j - 1; i >= 0; i--)
		{
			ans.pb({ i + 1,i + 2 });
			ab[i] ^= ab[i + 1];
		}
		a = ab;
		unordered_map<int, int> mp;
		bool YY = true;
		for (int i = 0; i < n; i++)
		{
			if (mp[a[i]]) { YY = false; break; }
			++mp[a[i]];
		}
		if (YY == false) {
			a = aa;
			continue;
		}
		while (1) {
			bool found = true;
			int mx = -1;
			int pos = -1;
			for (int i = 0; i < n - 1; i++)
				if (a[i] > a[i + 1]) {
					pos = i;
					break;
				}
			if (pos < 0) break;
			ans.pb({ pos + 2,pos + 1 });
			ans.pb({ pos + 1, pos + 2 });
			ans.pb({ pos + 2,pos + 1 });
			swap(a[pos], a[pos + 1]);
		}
		if (ans.size() < mn) {
			mn = ans.size();
			ans2 = ans;
		}
		a = aa;

	}
	ans = ans2;
	cout << ans.size() << '\n';
	for (auto to : ans)
		cout << to.F << " " << to.S << '\n';
}
void solve2() {
	int m = n;
	for (int i = 19; i >= 0; i--)
	{
		int st = 0;
		for (int j = 0; j < m - 1; j++)
		{
			if (a[j] & (1 << i) && a[j + 1] & (1 << i))
			{
				st = 1;
				ans.push_back({ j, j + 1 });
				a[j] ^= a[j + 1];
			}
			else if (a[j] & (1 << i))
			{
				st = 1;
				ans.push_back({ j + 1, j });
				ans.push_back({ j, j + 1 });
				a[j + 1] ^= a[j];
				a[j] ^= a[j + 1];
			}
		}
		if (st)
			m--;
	}
	cout << ans.size() << '\n';
	for (auto to : ans)
		cout << to.F << " " << to.S << '\n';
}

int main() {
	cin >> n >> type;
	a.resize(n);
	for (int i = 0; i < n; i++)
		cin >> a[i];
	if (type == 1) solve1();
	else solve2();
}

Compilation message

xorsort.cpp: In function 'void solve1()':
xorsort.cpp:53:9: warning: unused variable 'found' [-Wunused-variable]
   53 |    bool found = true;
      |         ^~~~~
xorsort.cpp:54:8: warning: unused variable 'mx' [-Wunused-variable]
   54 |    int mx = -1;
      |        ^~
xorsort.cpp:67:18: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   67 |   if (ans.size() < mn) {
      |       ~~~~~~~~~~~^~~~

Subtask #1
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Correct 75 ms 1104 KB Output is correct
5 Correct 73 ms 1008 KB Output is correct
6 Correct 70 ms 1000 KB Output is correct
7 Correct 66 ms 1004 KB Output is correct
8 Correct 63 ms 1024 KB Output is correct
9 Correct 66 ms 1036 KB Output is correct
10 Correct 63 ms 992 KB Output is correct
11 Correct 58 ms 896 KB Output is correct
12 Correct 61 ms 1416 KB Output is correct
13 Correct 57 ms 1348 KB Output is correct
14 Correct 62 ms 1364 KB Output is correct
15 Correct 59 ms 1416 KB Output is correct

Subtask #2
35.0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 0 ms 212 KB Output is correct
3 Correct 3 ms 340 KB Output is correct
4 Correct 75 ms 1104 KB Output is correct
5 Correct 73 ms 1008 KB Output is correct
6 Correct 70 ms 1000 KB Output is correct
7 Correct 66 ms 1004 KB Output is correct
8 Correct 63 ms 1024 KB Output is correct
9 Correct 66 ms 1036 KB Output is correct
10 Correct 63 ms 992 KB Output is correct
11 Correct 58 ms 896 KB Output is correct
12 Correct 61 ms 1416 KB Output is correct
13 Correct 57 ms 1348 KB Output is correct
14 Correct 62 ms 1364 KB Output is correct
15 Correct 59 ms 1416 KB Output is correct
16 Correct 1 ms 300 KB Output is correct
17 Correct 69 ms 1104 KB Output is correct
18 Correct 180 ms 1524 KB Output is correct
19 Correct 174 ms 1916 KB Output is correct
20 Correct 188 ms 1868 KB Output is correct
21 Correct 187 ms 1532 KB Output is correct
22 Correct 173 ms 1560 KB Output is correct
23 Correct 178 ms 1848 KB Output is correct
24 Correct 184 ms 1924 KB Output is correct
25 Correct 193 ms 1572 KB Output is correct
26 Correct 184 ms 1408 KB Output is correct
27 Correct 180 ms 1348 KB Output is correct
28 Correct 170 ms 1404 KB Output is correct
29 Correct 193 ms 1380 KB Output is correct
30 Correct 164 ms 1456 KB Output is correct

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Incorrect 1 ms 212 KB Integer 0 violates the range [1, 5]
2 Halted 0 ms 0 KB -