4주차 문제풀이(2)

이강민(그래프)/prob4.cpp

@@ -0,0 +1,129 @@
+#include <iostream>
+#include <vector>
+#include <queue>
+using namespace std;
+int N; //������ ũ��
+int color = 1; //����� ����
+vector<vector<int>> map;
+vector<vector<int>> continent_color;
+int dir_x[4] = { 0, 0, -1, 1 }; //�� �� �� ��
+int dir_y[4] = { 1, -1, 0, 0 };
+void obeserveContinent() //���� �ٸ� ����� �����ϱ� ���� �ٸ� ������ ��ĥ�ϴ� �Լ�
+{
+	continent_color.resize(N, vector<int>(N));
+	queue<pair<int, int>> q;
+
+	for (int i = 0; i < N; i++)
+	{
+		for (int j = 0; j < N; j++)
+		{
+			if (map[i][j] == 1 && continent_color[i][j] == 0)
+			{
+				q.push(make_pair(i, j));
+				continent_color[i][j] = color; //�湮���� ǥ��, ����� ��ĥ�Ͽ� �ٸ� ����� �����ϱ�
+				while (!q.empty())
+				{
+					int x = q.front().first;
+					int y = q.front().second;
+					q.pop();
+					for (int k = 0; k < 4; k++)
+					{
+						int new_x = x + dir_x[k];
+						int new_y = y + dir_y[k];
+						if (0 <= new_x && new_x < N && 0 <= new_y && new_y < N)
+						{
+							if (continent_color[new_x][new_y] == 0 && map[new_x][new_y] == 1)
+							{
+								q.push(make_pair(new_x, new_y));
+								continent_color[new_x][new_y] = color; //�湮���� ǥ��, ����� ��ĥ�Ͽ� �ٸ� ����� �����ϱ�
+							}
+						}
+					}
+				}
+				color++;
+			}
+		}
+	}
+	return;
+}
+int calculate_min_distance(int color)
+{
+	for (int i = 0; i < N; i++) //������ 0���� �ʱ�ȭ
+	{
+		for (int j = 0; j < N; j++)
+		{
+			map[i][j] = 0;
+		}
+	}
+	queue<pair<int, int>> q;
+	for (int i = 0; i < N; i++)
+	{
+		for (int j = 0; j < N; j++)
+		{
+			if (continent_color[i][j] == color) //����� ������ �ٴ� ĭ�� ť�� ���� ����
+			{
+				for (int k = 0; k < 4; k++)
+				{
+					int new_x = i + dir_x[k];
+					int new_y = j + dir_y[k];
+					if (0 <= new_x && new_x < N && 0 <= new_y && new_y < N)
+					{
+						if (continent_color[new_x][new_y] == 0)
+						{
+							q.push(make_pair(new_x, new_y));
+							map[new_x][new_y] = 1; //������� �ش� ĭ���� �̵��ϴ� �� �ʿ��� �Ÿ�
+						}
+					}
+				}
+			}
+		}
+	}
+	int count = 100000;
+	while (!q.empty())
+	{
+		int x = q.front().first;
+		int y = q.front().second;
+		q.pop();
+		for (int k = 0; k < 4; k++)
+		{
+			int new_x = x + dir_x[k];
+			int new_y = y + dir_y[k];
+			if (0 <= new_x && new_x < N && 0 <= new_y && new_y < N)
+			{
+				if (continent_color[new_x][new_y] == 0 && map[new_x][new_y] == 0)
+				{
+					q.push(make_pair(new_x, new_y));
+					map[new_x][new_y] = map[x][y] + 1; //�ش� ĭ���� �����ϴµ� �ʿ��� �Ÿ� ���ϱ�
+				}
+				if (continent_color[new_x][new_y] != color && continent_color[new_x][new_y] != 0 && count > map[x][y])
+				{
+					count = map[x][y];
+				}
+			}
+		}
+	}
+	return count;
+}
+int main()
+{
+
+	cin >> N;
+	map.resize(N, vector<int>(N)); //2���� ���� �ʱ�ȭ
+
+	for (int i = 0; i < N; i++) //���� ������ �Է� �ޱ�
+	{
+		for (int j = 0; j < N; j++)
+		{
+			cin >> map[i][j];
+		}
+	}
+	obeserveContinent(); //����� ���� �ٸ� ������ ��ĥ��
+	int min = calculate_min_distance(1);
+	for (int i = 2; i < color; i++)
+	{
+		int result = calculate_min_distance(i);
+		if (min > result)
+			min = result;
+	}
+	cout << min;
+}

이강민(그래프)/prob5(fix).cpp

@@ -0,0 +1,46 @@
+#include <iostream>
+#include <utility>
+using namespace std;
+pair<char, char> tree[26]; //���� �ڽİ� ������ �ڽ��� ������ �� �ִ� ���Ĺ� Ʈ�� ����
+void preorder(char root) //���� ��ȸ root-left-right
+{
+	if (root == '.')
+		return;
+	cout << root;
+	preorder(tree[root - 'A'].first);
+	preorder(tree[root - 'A'].second);
+}
+void inorder(char root) //���� ��ȸ  left-root-right
+{
+	if (root == '.')
+		return;
+	inorder(tree[root - 'A'].first);
+	cout << root;
+	inorder(tree[root - 'A'].second);
+}
+void postorder(char root) //���� ��ȸ left-right-root
+{
+	if (root == '.')
+		return;
+	postorder(tree[root - 'A'].first);
+	postorder(tree[root - 'A'].second);
+	cout << root;
+}
+int main()
+{
+	int N; //Ʈ���� ��� ����
+	cin >> N;
+	for (int i = 0; i < N; i++) //Ʈ�� ���� �Է� �ޱ�
+	{
+		char root, left, right; //�Է� 1,2,3
+		cin >> root >> left >> right;
+		tree[root - 'A'].first = left;
+		tree[root - 'A'].second = right;
+	}
+	preorder('A');
+	cout << '\n';
+	inorder('A');
+	cout << '\n';
+	postorder('A');
+	return 0;
+}

이강민(그래프)/prob5.cpp

@@ -0,0 +1,48 @@
+#include <iostream>
+#include <utility>
+using namespace std;
+pair<char, char> tree[26]; //���� �ڽİ� ������ �ڽ��� ������ �� �ִ� ���Ĺ� Ʈ�� ����
+void preorder(char root) //���� ��ȸ root-left-right
+{
+	if (root == '.')
+		return;
+	cout << root;
+	preorder(tree[root - 'A'].first);
+	preorder(tree[root - 'A'].second);
+}
+void inorder(char root) //���� ��ȸ  left-root-right
+{
+	if (tree[root - 'A'].first != '.')
+		inorder(tree[root - 'A'].first);
+	cout << root;
+	if (tree[root - 'A'].second != '.')
+		inorder(tree[root - 'A'].second);
+	return;
+}
+void postorder(char root) //���� ��ȸ left-right-root
+{
+	if (tree[root - 'A'].first != '.')
+		postorder(tree[root - 'A'].first);
+	if (tree[root - 'A'].second != '.')
+		postorder(tree[root - 'A'].second);
+	cout << root;
+	return;
+}
+int main()
+{
+	int N; //Ʈ���� ��� ����
+	cin >> N;
+	for (int i = 0; i < N; i++) //Ʈ�� ���� �Է� �ޱ�
+	{
+		char root, left, right; //�Է� 1,2,3
+		cin >> root >> left >> right;
+		tree[root - 'A'].first = left;
+		tree[root - 'A'].second = right;
+	}
+	preorder('A');
+	cout << '\n';
+	inorder('A');
+	cout << '\n';
+	postorder('A');
+	return 0;
+}

이강민(그래프)/prob6.cpp

@@ -0,0 +1,38 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+vector<int> graph[100001];
+bool visited[100001];
+int parent[100001];
+int N;
+void DFS(int root)
+{
+	visited[root] = 1;
+	for (int i = 0; i < graph[root].size(); i++) //����� ��� ��������
+	{
+		int V = graph[root][i];
+		if (!visited[V]) //�湮���� ���� ���
+		{
+			parent[V] = root;
+			DFS(V);
+		}
+	}
+	return;
+}
+int main()
+{
+	cin >> N;
+	for (int i = 0; i < N - 1; i++)
+	{
+		int v1, v2;
+		cin >> v1 >> v2;
+		graph[v1].push_back(v2); //���� v1�� v2�� ������ �ǹ�
+		graph[v2].push_back(v1); //�ݴ�ε� ����
+	}
+	DFS(1);
+	for (int i = 2; i <= N; i++)
+	{
+		cout << parent[i] << '\n';
+	}
+	return 0;
+}

이강민(그래프)/prob7.cpp

@@ -0,0 +1,50 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+vector<pair<int, int>> graph[100001];
+bool visited[100001];
+int leaf, max_d;
+void DFS(int root, int dist)
+{
+	visited[root] = 1;
+	for (int i = 0; i < graph[root].size(); i++) //����� ��� ��������
+	{
+		int V = graph[root][i].first;
+		int d = graph[root][i].second;
+		if (!visited[V]) //�湮���� ���� ���
+		{
+			DFS(V, dist + d);
+		}
+	}
+	if (dist > max_d)
+	{
+		leaf = root;
+		max_d = dist;
+	}
+	return;
+}
+int main()
+{
+	int N;
+	cin >> N;
+	for (int i = 1; i <= N; i++) // 1 ~ N ����
+	{
+		int v1, v2, dist;
+		cin >> v1;
+		while (1) //-1�� �Էµ� �� ���� ����� ������ ���� �Է¹ޱ�
+		{
+			cin >> v2;
+			if (v2 == -1)
+				break;
+			cin >> dist;
+			graph[v1].push_back(make_pair(v2, dist));
+		}
+	}
+	DFS(1, 0); //������� �
+	for (int j = 1; j <= N; j++) //visied �迭 �ʱ�ȭ
+		visited[j] = 0;
+	max_d = 0; //�ִ밪 �ʱ�ȭ
+	DFS(leaf, 0); //������忡�� DFS�ϱ�
+	cout << max_d;
+	return 0;
+}

이강민(그래프)/prob8.cpp

@@ -0,0 +1,45 @@
+#include <iostream>
+#include <vector>
+using namespace std;
+vector<pair<int, int>> graph[10001];
+bool visited[10001];
+int leaf, max_d;
+void DFS(int root, int dist)
+{
+	visited[root] = 1;
+	for (int i = 0; i < graph[root].size(); i++) //����� ��� ��������
+	{
+		int V = graph[root][i].first;
+		int d = graph[root][i].second;
+		if (!visited[V]) //�湮���� ���� ���
+		{
+			DFS(V, dist + d);
+		}
+	}
+	if (dist > max_d)
+	{
+		leaf = root;
+		max_d = dist;
+	}
+	return;
+}
+int main()
+{
+	int N;
+	cin >> N;
+	for (int i = 0; i < N - 1; i++) // 1 ~ N ����
+	{
+		int v1, v2, dist;
+		cin >> v1 >> v2 >> dist;
+		graph[v1].push_back(make_pair(v2, dist));
+		graph[v2].push_back(make_pair(v1, dist));
+
+	}
+	DFS(1, 0); //������� �
+	for (int j = 1; j <= N; j++) //visied �迭 �ʱ�ȭ
+		visited[j] = 0;
+	max_d = 0; //�ִ밪 �ʱ�ȭ
+	DFS(leaf, 0); //������忡�� DFS�ϱ�
+	cout << max_d;
+	return 0;
+}