Submission #839898

# Submission time Handle Problem Language Result Execution time Memory
839898 2023-08-30T20:29:03 Z happypotato Longest Trip (IOI23_longesttrip) C++17
15 / 100
1000 ms 896 KB
#include "longesttrip.h"
 
#include <bits/stdc++.h>
#pragma GCC optimize("O2")
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;
}
# Verdict Execution time Memory Grader output
1 Correct 1 ms 208 KB Output is correct
2 Correct 214 ms 676 KB Output is correct
# 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
# Verdict Execution time Memory Grader output
1 Correct 12 ms 208 KB Output is correct
2 Correct 30 ms 208 KB Output is correct
3 Correct 154 ms 336 KB Output is correct
4 Correct 530 ms 336 KB Output is correct
5 Correct 913 ms 896 KB Output is correct
6 Correct 12 ms 208 KB Output is correct
7 Correct 30 ms 208 KB Output is correct
8 Correct 129 ms 476 KB Output is correct
9 Correct 304 ms 336 KB Output is correct
10 Correct 814 ms 576 KB Output is correct
11 Correct 775 ms 700 KB Output is correct
12 Correct 786 ms 656 KB Output is correct
13 Correct 899 ms 656 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 11 ms 208 KB Output is correct
2 Correct 42 ms 208 KB Output is correct
3 Correct 148 ms 344 KB Output is correct
4 Correct 342 ms 460 KB Output is correct
5 Correct 756 ms 568 KB Output is correct
6 Correct 12 ms 208 KB Output is correct
7 Correct 42 ms 208 KB Output is correct
8 Correct 174 ms 336 KB Output is correct
9 Correct 353 ms 336 KB Output is correct
10 Execution timed out 1111 ms 640 KB Time limit exceeded
11 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 11 ms 208 KB Output is correct
2 Correct 22 ms 208 KB Output is correct
3 Partially correct 191 ms 336 KB Output is partially correct
4 Partially correct 400 ms 388 KB Output is partially correct
5 Partially correct 956 ms 692 KB Output is partially correct
6 Correct 11 ms 208 KB Output is correct
7 Correct 42 ms 208 KB Output is correct
8 Partially correct 223 ms 336 KB Output is partially correct
9 Partially correct 373 ms 372 KB Output is partially correct
10 Partially correct 817 ms 568 KB Output is partially correct
11 Partially correct 927 ms 656 KB Output is partially correct
12 Partially correct 744 ms 584 KB Output is partially correct
13 Partially correct 670 ms 656 KB Output is partially correct
14 Correct 13 ms 208 KB Output is correct
15 Correct 18 ms 208 KB Output is correct
16 Correct 72 ms 208 KB Output is correct
17 Partially correct 117 ms 336 KB Output is partially correct
18 Partially correct 211 ms 404 KB Output is partially correct
19 Partially correct 228 ms 336 KB Output is partially correct
20 Partially correct 226 ms 464 KB Output is partially correct
21 Correct 17 ms 208 KB Output is correct
22 Correct 16 ms 208 KB Output is correct
23 Correct 30 ms 208 KB Output is correct
24 Correct 42 ms 208 KB Output is correct
25 Correct 43 ms 208 KB Output is correct
26 Partially correct 183 ms 340 KB Output is partially correct
27 Partially correct 239 ms 336 KB Output is partially correct
28 Partially correct 269 ms 456 KB Output is partially correct
29 Partially correct 335 ms 352 KB Output is partially correct
30 Partially correct 379 ms 380 KB Output is partially correct
31 Partially correct 341 ms 392 KB Output is partially correct
32 Correct 12 ms 208 KB Output is correct
33 Correct 10 ms 208 KB Output is correct
34 Correct 27 ms 208 KB Output is correct
35 Correct 23 ms 208 KB Output is correct
36 Correct 29 ms 208 KB Output is correct
37 Partially correct 196 ms 584 KB Output is partially correct
38 Partially correct 210 ms 336 KB Output is partially correct
39 Partially correct 211 ms 336 KB Output is partially correct
40 Partially correct 337 ms 388 KB Output is partially correct
41 Partially correct 305 ms 336 KB Output is partially correct
42 Partially correct 298 ms 336 KB Output is partially correct
43 Partially correct 827 ms 620 KB Output is partially correct
44 Partially correct 747 ms 692 KB Output is partially correct
45 Partially correct 796 ms 732 KB Output is partially correct
46 Partially correct 657 ms 680 KB Output is partially correct
47 Partially correct 779 ms 652 KB Output is partially correct
48 Partially correct 794 ms 712 KB Output is partially correct
49 Partially correct 787 ms 652 KB Output is partially correct
50 Partially correct 881 ms 664 KB Output is partially correct
51 Partially correct 901 ms 652 KB Output is partially correct
52 Partially correct 893 ms 512 KB Output is partially correct
53 Partially correct 919 ms 676 KB Output is partially correct
54 Partially correct 852 ms 648 KB Output is partially correct
55 Partially correct 862 ms 752 KB Output is partially correct
56 Partially correct 956 ms 644 KB Output is partially correct
57 Partially correct 995 ms 660 KB Output is partially correct
58 Partially correct 837 ms 848 KB Output is partially correct
59 Execution timed out 1042 ms 680 KB Time limit exceeded
60 Halted 0 ms 0 KB -