Submission #1075913

#	Time	Username	Problem	Language	Result	Execution time	Memory
1075913		NeroZein	Simurgh (IOI17_simurgh)	C++17	13 / 100	558 ms	604 KiB

simurgh

#include "simurgh.h"
#include <bits/stdc++.h>
using namespace std;

vector<int> find_roads(int n, vector<int> eu, vector<int> ev) {
	
	int cc;
	vector<int> p(n), sz(n);
	
	function<int(int)> get = [&](int v) {
		return p[v] = (p[v] == v ? v : get(p[v]));
	};
	
	auto unite = [&](int u, int v) {
		u = get(u); v = get(v);
		if (u == v) {
			return false;
		}
		if (sz[u] > sz[v]) {
			swap(u, v);
		}
		--cc;
		p[u] = v;
		sz[v] += sz[u];
		return true;
	};
	
	auto init_dsu = [&]() {
		cc = n;
		iota(p.begin(), p.end(), 0);
		fill(sz.begin(), sz.end(), 1);
	};
	
	int m = (int) eu.size();
	for (int i = 0; i < (1 << m); ++i) {
		init_dsu();
		bool ok = true; 
		vector<int> in_tree;
		for (int j = 0; j < m; ++j) {
			if (i >> j & 1) {
				in_tree.push_back(j); 
				ok &= unite(eu[j], ev[j]);
			}
		}
		if (cc > 1 || !ok) {
			continue; 
		}
		assert(in_tree.size() == n - 1);
		if (count_common_roads(in_tree) == n - 1) {
			return in_tree;
		}
	}
	assert(false); 
}
//~ int common = count_common_roads(r);

Compilation message (stderr)

In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from simurgh.cpp:2:
simurgh.cpp: In function 'std::vector<int> find_roads(int, std::vector<int>, std::vector<int>)':
simurgh.cpp:48:25: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   48 |   assert(in_tree.size() == n - 1);
      |          ~~~~~~~~~~~~~~~^~~~~~~~

• Subtask 1: 13 / 13
• Subtask 2: 0 / 17
• Subtask 3: 0 / 21
• Subtask 4: 0 / 19
• Subtask 5: 0 / 30