oj.uz

Submission #201976

# Submission time Handle Problem Language Result Execution time Memory
201976 2020-02-12T23:42:42 Z Fischer Tropical Garden (IOI11_garden) C++14
0 / 100
 6 ms 504 KB 
#include <bits/stdc++.h>
#include "garden.h"
#include "gardenlib.h"
using namespace std;

int _left(int x) {
	return x<<1;
}

int _right(int x) {
	return x<<1|1;
}

bool is_left(int x) {
	return _left(x/2) == x;
}

vector<int> make_functional_graph(int n, int E[][2], int m) {
	vector<int> F(2 * n);
	vector<vector<int>> best(n);
	for (int i = 0; i < m; ++i) {
		int u = E[i][0], v = E[i][1];
		best[u].emplace_back(v);
		best[v].emplace_back(u);
	}
	for (int i = 0; i < n; ++i) {
		if (best[i].size() == 1) {
			best[i].emplace_back(best[i][0]);
		}
	}
	for (int i = 0; i < n; ++i) {
		int a = best[i][0], b = best[i][1];
		F[_left(i)] = best[a][0] == i ? _right(a) : _left(a);
		F[_right(i)] = best[b][0] == i ? _right(b) : _left(b);
	}
	return F;
}

vector<vector<int>> make_reverse_functional(vector<int> F) {
	vector<vector<int>> Gt;
	for (int i = 0; i < F.size(); ++i) {	
		Gt[F[i]].emplace_back(i);
	}
	return Gt;
}

const int inf = 1e9;
vector<int> bfs(vector<vector<int>> G, int src) {
	vector<int> dis(G.size(), inf);
	dis[src] = 0;
	queue<int> Q;
	Q.push(src);
	while (not Q.empty()) {
		int q = Q.front(); Q.pop();
		for (int v : G[q]) {
			if (dis[q] + 1 < dis[v]) {
				dis[v] = dis[q] + 1;
				Q.push(v);
			}
		}
	}
	return dis;
}

vector<int> get_cycle_from_functional(vector<int> F, int x) {
	vector<int> cycle;
	vector<bool> vis(F.size());
	while (not vis[x]) {
		vis[x] = 1;
		x = F[x];
	}
	do {
		cycle.emplace_back(x);
		x = F[x];
	} while (x != F[x]);
	return cycle;
}

bool is_in(int t, vector<int> v) {
	for (int e : v) {
		if (e == _left(t) or e == _right(t)) {
			return 1;
		}
	}
	return 0;
}

vector<int> solve(vector<int> F, int x) {
	auto dis = bfs(make_reverse_functional(F), x);
	auto cycle = get_cycle_from_functional(F, x);
	int cycle_len = cycle.size();
	int n = F.size();
	vector<int> ans(2 * n);
	if (is_in(x, cycle)) {
		for (int i = 0; i < 2 * n; ++i) {
			if (dis[i] >= inf) continue;
			if (not is_left(i)) continue; 
			ans[dis[i]] += 1;
		}
		for (int i = 0; i + cycle_len < 2 * n; ++i) {
			ans[i + cycle_len] += ans[i];
		}
	} else {
		for (int i = 0; i < 2 * n; ++i) {
			if (dis[i] >= inf) continue;
			if (not is_left(i)) continue;
			ans[dis[i]] += 1;
		}
	}
	return ans;
}

void count_routes(int n, int m, int p, int R[][2], int q, int Q[]) {
	auto G = make_functional_graph(n, R, m);
	auto ans1 = solve(G, _left(p));
	auto ans2 = solve(G, _right(p));
	for (int i = 0; i < q; ++i) {
		answer(ans1[Q[i] % (2 * n)] + ans2[Q[i] % (2 * n)]);
	}
}

Compilation message

garden.cpp: In function 'std::vector<std::vector<int> > make_reverse_functional(std::vector<int>)':
garden.cpp:41:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < F.size(); ++i) { 
                  ~~^~~~~~~~~~

Subtask #1
0 / 49.0

# Verdict Execution time Memory Grader output
1 Runtime error 6 ms 504 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -

Subtask #2
0 / 20.0

# Verdict Execution time Memory Grader output
1 Runtime error 6 ms 504 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -

Subtask #3
0 / 31.0

# Verdict Execution time Memory Grader output
1 Runtime error 6 ms 504 KB Execution killed with signal 11 (could be triggered by violating memory limits)
2 Halted 0 ms 0 KB -