oj.uz

Submission #839831

# Submission time Handle Problem Language Result Execution time Memory
839831 2023-08-30T17:58:12 Z happypotato Longest Trip (IOI23_longesttrip) C++17
15 / 100
 1000 ms 880 KB 
#include "longesttrip.h"
 
#include <bits/stdc++.h>
using namespace std;
// #define int long long // remove when necessary
#define pii pair<int, int>
#define ff first
#define ss second
#define pb push_back
#define ll long long
const int mxN = 256;
vector<int> adj[mxN];
vector<int> grp[mxN];
bool con[mxN][mxN];
int n;
int dsupp[mxN];
vector<int> nxt[mxN];
bool vis[mxN];
void resetvis() {
	for (int i = 0; i < n; i++) vis[i] = false;
}
void reset() {
	for (int i = 0; i < n; i++) {
		adj[i].clear();
		grp[i].clear();
		for (int j = 0; j < n; j++) {
			con[i][j] = 0;
		}
		dsupp[i] = i;
		nxt[i].clear();
		vis[i] = false;
	}
}
int DSUFind(int u) {
	if (dsupp[u] == u) return u;
	return (dsupp[u] = DSUFind(dsupp[u]));
}
void DSUMerge(int u, int v) {
	u = DSUFind(u); v = DSUFind(v);
	if (u != v) dsupp[v] = u;
}
vector<int> GetPath(int st) {
	resetvis();
	vector<int> res;
	while (true) {
		res.pb(st);
		vis[st] = true;
		bool found = false;
		for (int &v : nxt[st]) {
			if (!vis[v]) {
				st = v;
				found = true;
				break;
			}
		}
		if (!found) break;
	}
	return res;
}
vector<int> MakePath(vector<int> &v) {
	if (v.size() == 1) return {v[0]};
	if (v.size() == 2) {
		if (con[v[0]][v[1]]) return {v[0], v[1]};
		else return {v[0]};
	}
	if (v.size() == 3) {
		if (con[v[0]][v[1]] && con[v[0]][v[2]]) return {v[1], v[0], v[2]};
		if (con[v[0]][v[1]] && con[v[1]][v[2]]) return {v[0], v[1], v[2]};
		if (con[v[0]][v[2]] && con[v[1]][v[2]]) return {v[0], v[2], v[1]};
		if (con[v[0]][v[1]]) return {v[0], v[1]};
		if (con[v[0]][v[2]]) return {v[0], v[2]};
		if (con[v[1]][v[2]]) return {v[1], v[2]};
		return {v[0]};
	}
	for (int i = 0; i < n; i++) {
		nxt[i].clear();
	}
	pair<pii, pii> cur = {{v[0], v[0]}, {v[1], v[1]}};
	for (int i = 2; i < (int)(v.size()); i++) {
		if (con[cur.ff.ff][cur.ss.ff]) {
			nxt[cur.ff.ff].pb(cur.ss.ff);
			nxt[cur.ss.ff].pb(cur.ff.ff);
			cur.ff.ff = cur.ss.ss;
			cur.ss = {v[i], v[i]};
		} else if (con[cur.ff.ff][v[i]]) {
			nxt[cur.ff.ff].pb(v[i]);
			nxt[v[i]].pb(cur.ff.ff);
			cur.ff.ff = v[i];
		} else if (con[cur.ss.ff][v[i]]) {
			nxt[cur.ss.ff].pb(v[i]);
			nxt[v[i]].pb(cur.ss.ff);
			cur.ss.ff = v[i];
		} else {
			while (true) continue;
		}
	}
	int st;
	if (con[cur.ff.ff][cur.ss.ff]) {
		nxt[cur.ff.ff].pb(cur.ss.ff);
		nxt[cur.ss.ff].pb(cur.ff.ff);
		st = cur.ff.ss;
	} else if (con[cur.ff.ff][cur.ss.ss]) {
		nxt[cur.ff.ff].pb(cur.ss.ss);
		nxt[cur.ss.ss].pb(cur.ff.ff);
		st = cur.ff.ss;
	} else if (con[cur.ff.ss][cur.ss.ff]) {
		nxt[cur.ff.ss].pb(cur.ss.ff);
		nxt[cur.ss.ff].pb(cur.ff.ss);
		st = cur.ff.ff;
	} else if (con[cur.ff.ss][cur.ss.ss]) {
		nxt[cur.ff.ss].pb(cur.ss.ss);
		nxt[cur.ss.ss].pb(cur.ff.ss);
		st = cur.ff.ff;
	} else {
		vector<int> res[2];
		res[0] = GetPath(cur.ff.ff);
		res[1] = GetPath(cur.ss.ff);
 
		// cerr << "res0: ";
		// for (int &x : res[0]) cerr << x << ' ';
		// cerr << endl;
		// cerr << "res1: ";
		// for (int &x : res[1]) cerr << x << ' ';
		// cerr << endl;
 
		bool found = false;
		for (int i = 0; i < (int)(res[0].size()); i++) {
			for (int j = 0; j < (int)(res[1].size()); j++) {
				if (con[res[0][i]][res[1][j]]) {
					// cerr << "FOUND " << res[0][i] << ' ' << res[1][j] << endl;
					nxt[res[0][i]].pb(res[1][j]);
					nxt[res[1][j]].pb(res[0][i]);
 
					if (res[0].size() >= 3) {
						nxt[cur.ff.ff].pb(cur.ff.ss);
						nxt[cur.ff.ss].pb(cur.ff.ff);
						// cerr << "RES0 ";
						// for (int &x : res[0]) cerr << x << ' ';
						// cerr << endl;
						st = (i == 0 ? res[0].back() : res[0][i - 1]);
						// cerr << "ST " << st << endl;
						vector<int>::iterator it;
						for (it = nxt[st].begin(); it != nxt[st].end(); ++it) {
							if (*it == res[0][i]) {
								nxt[st].erase(it);
								break;
							}
						}
						for (it = nxt[res[0][i]].begin(); it != nxt[res[0][i]].end(); ++it) {
							if (*it == st) {
								nxt[res[0][i]].erase(it);
								break;
							}
						}
					} else {
						st = (res[0].size() == 2 ? res[0][i ^ 1] : res[0][i]);
					}
 
					if (res[1].size() >= 3) {
						nxt[cur.ss.ff].pb(cur.ss.ss);
						nxt[cur.ss.ss].pb(cur.ss.ff);
						int tar = (j == 0 ? res[1].back() : res[1][j + 1]);
						vector<int>::iterator it;
						for (it = nxt[tar].begin(); it != nxt[tar].end(); ++it) {
							if (*it == res[1][j]) {
								nxt[tar].erase(it);
								break;
							}
						}
						for (it = nxt[res[1][j]].begin(); it != nxt[res[1][j]].end(); ++it) {
							if (*it == tar) {
								nxt[res[1][j]].erase(it);
								break;
							}
						}
					}
 
					found = true;
					break;
				}
			}
			if (found) break;
		}
		if (!found) {
			while (true) continue;
		}
	}
 
	// cerr << "find path for: ";
	// for (int &x : v) cerr << x << ' ';
	// cerr << endl;
	
	vector<int> res = GetPath(st);
 
	// cerr << "st: " << st << endl;
	// cerr << "result: ";
	// for (int &x : res) cerr << x << ' ';
	// cerr << endl;
 
	return res;
}
vector<int> longest_trip(int N, int D)
{
	n = N;
	reset();
	if (D == 3) {
		vector<int> res(n);
		for (int i = 0; i < n; i++) res[i] = i;
		return res;
	}
	for (int i = 0; i < n; i++) {
		for (int j = i + 1; j < n; j++) {
			if (are_connected({i}, {j})) {
				adj[i].pb(j);
				adj[j].pb(i);
				con[i][j] = con[j][i] = true;
				DSUMerge(i, j);
			}
		}
	}
	for (int i = 0; i < n; i++) {
		grp[DSUFind(i)].pb(i);
	}
	vector<int> best = {};
	for (int i = 0; i < n; i++) {
		if (grp[i].empty()) continue;
		vector<int> res = MakePath(grp[i]);
		if (res.size() > best.size()) {
			best = res;
		}
	}
	return best;
}
// after contest 60 submission

Subtask #0
0.0 / 0.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 208 KB Output is correct
2 Correct 229 ms 584 KB Output is correct

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 4 ms 208 KB Output is correct
2 Correct 1 ms 208 KB Output is correct
3 Correct 1 ms 208 KB Output is correct
4 Correct 1 ms 336 KB Output is correct
5 Correct 1 ms 336 KB Output is correct

Subtask #2
10.0 / 10.0

# Verdict Execution time Memory Grader output
1 Correct 8 ms 208 KB Output is correct
2 Correct 36 ms 208 KB Output is correct
3 Correct 170 ms 336 KB Output is correct
4 Correct 426 ms 404 KB Output is correct
5 Correct 851 ms 800 KB Output is correct
6 Correct 10 ms 208 KB Output is correct
7 Correct 30 ms 208 KB Output is correct
8 Correct 174 ms 336 KB Output is correct
9 Correct 256 ms 336 KB Output is correct
10 Correct 806 ms 612 KB Output is correct
11 Correct 813 ms 824 KB Output is correct
12 Correct 883 ms 788 KB Output is correct
13 Correct 783 ms 704 KB Output is correct

Subtask #3
0.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 208 KB Output is correct
2 Correct 32 ms 208 KB Output is correct
3 Correct 150 ms 336 KB Output is correct
4 Correct 426 ms 392 KB Output is correct
5 Correct 779 ms 648 KB Output is correct
6 Correct 10 ms 208 KB Output is correct
7 Correct 33 ms 208 KB Output is correct
8 Correct 150 ms 336 KB Output is correct
9 Correct 276 ms 376 KB Output is correct
10 Correct 804 ms 572 KB Output is correct
11 Correct 825 ms 528 KB Output is correct
12 Correct 760 ms 700 KB Output is correct
13 Correct 760 ms 592 KB Output is correct
14 Correct 6 ms 332 KB Output is correct
15 Correct 11 ms 208 KB Output is correct
16 Correct 58 ms 208 KB Output is correct
17 Correct 84 ms 208 KB Output is correct
18 Correct 105 ms 336 KB Output is correct
19 Correct 320 ms 388 KB Output is correct
20 Correct 309 ms 396 KB Output is correct
21 Correct 697 ms 616 KB Output is correct
22 Correct 867 ms 672 KB Output is correct
23 Correct 883 ms 656 KB Output is correct
24 Correct 780 ms 880 KB Output is correct
25 Correct 16 ms 208 KB Output is correct
26 Correct 13 ms 208 KB Output is correct
27 Correct 28 ms 208 KB Output is correct
28 Correct 36 ms 208 KB Output is correct
29 Correct 31 ms 332 KB Output is correct
30 Correct 212 ms 364 KB Output is correct
31 Correct 218 ms 348 KB Output is correct
32 Correct 226 ms 336 KB Output is correct
33 Correct 290 ms 388 KB Output is correct
34 Correct 321 ms 392 KB Output is correct
35 Correct 334 ms 392 KB Output is correct
36 Correct 767 ms 792 KB Output is correct
37 Correct 853 ms 648 KB Output is correct
38 Execution timed out 1148 ms 600 KB Time limit exceeded
39 Halted 0 ms 0 KB -

Subtask #4
0.0 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 208 KB Output is correct
2 Correct 46 ms 208 KB Output is correct
3 Partially correct 169 ms 336 KB Output is partially correct
4 Partially correct 521 ms 516 KB Output is partially correct
5 Execution timed out 1050 ms 696 KB Time limit exceeded
6 Halted 0 ms 0 KB -