Traffic_light.cpp

#include<iostream>
#include<vector>


// "Traffic light" task, http://acmp.ru/index.asp?main=task&id_task=124

class Graph
{
public:
	typedef size_t Vertex;
	Graph(size_t vertex_count, bool is_directed)
	{
		vertex_count_ = vertex_count;
		is_directed_ = is_directed;
	}

	size_t getVertexCount() const
	{
		return vertex_count_;
	}

	size_t getEdgeCount() const
	{
		return edge_count_;
	}

	virtual std::vector<Vertex> getNeighbors(const Vertex& v) const = 0;

	virtual void addEdge(const Vertex& start, const Vertex& finish)
	{
		edge_count_++;
	}
	virtual size_t getNeighborsCount(const Vertex& v) const = 0;

protected:
	bool is_directed_;
	size_t vertex_count_,
		edge_count_;
};


class GraphAdjList : public Graph
{

public:
	GraphAdjList(const size_t vertex_count, bool is_directed) :
		Graph(vertex_count, is_directed)
	{
		adj_list_ = std::vector<std::vector<Vertex>>(vertex_count);
	}

	void addEdge(const Vertex& start, const Vertex& finish)
	{
		Graph::addEdge(start, finish);
		adj_list_[start].push_back(finish);
		if (!is_directed_)
			adj_list_[finish].push_back(start);
	}

	std::vector<Vertex> getNeighbors(const Vertex& v) const override
	{
		return adj_list_[v];
	}

	size_t getNeighborsCount(const Vertex&  v) const override
	{
		return adj_list_[v].size();
	}

	void printGraph() const
	{
		std::cout << "Print\n";
		std::cout << vertex_count_;
		for (size_t i = 0; i < vertex_count_; i++)
		{
			for (auto k : adj_list_[i])
				std::cout << k << " ";
			std::cout << std::endl;
		}
	}

private:
	std::vector<std::vector<Vertex>> adj_list_;
};

int main()
{
	int n, m;
	std::cin >> n;
	std::cin >> m;
	GraphAdjList g(n, false);
	for (size_t i = 0; i < m; i++)
	{
		size_t a, b;
		std::cin >> a;
		std::cin >> b;
		g.addEdge(a - 1, b - 1);
	}
	for (int i = 0; i < n; i++)
	{
		std::cout << g.getNeighborsCount(i) << " ";
	}
}