dijkstra 왤케 어려워

Basic_Of_Algorithm/src/Today_22_06_02/arrow.java

@@ -0,0 +1,91 @@
+package Today_22_06_02;
+
+import java.util.ArrayList;
+import java.util.Collections;
+
+public class arrow {
+
+	static int apeach[];
+	static int ryan[];
+	static int count;
+	static int maxvalue = 0;
+	static ArrayList<int[]> answerList = new ArrayList<>();
+
+	public static void main(String[] args) {
+
+		int[]info = {0,0,1,2,0,1,1,1,1,1,1};
+		int n = 9;
+
+		apeach = info.clone();
+		count = n;
+		ryan = new int[info.length];
+
+		dfs(0,0);
+
+		int [] answer;
+
+		if(answerList.isEmpty()) answer = new int[] {-1};
+
+		else {
+
+			Collections.sort(answerList,(o1,o2)->{
+
+				for(int i=10;i>-1;i--) {
+					if(o1[i]!=o2[i]) return o2[i] - o1[i];
+				}
+
+				return 0;
+
+			});
+
+			answer = new int[apeach.length];
+
+			for(int i=0;i<apeach.length;i++) answer[i] = answerList.get(0)[i];
+
+
+			for(int i : answer)System.out.print(i+", ");
+		}
+
+
+
+
+
+	}
+	static void dfs(int start, int arrow) {
+
+		if(arrow==count) {
+
+			int r = 0;
+			int a = 0;
+
+			for(int i=0;i<11;i++) {
+				if(ryan[i]==0 && apeach[i]==0) continue;
+
+				if(ryan[i]>apeach[i]) r += 10 - i;
+				else a += 10 - i;
+			}
+
+			if(r>a) {
+				int diff = r - a;
+				if(diff>maxvalue) {
+					maxvalue = diff;
+					answerList.clear();
+					answerList.add(ryan.clone());
+
+				}else if(diff==maxvalue) {
+					answerList.add(ryan.clone());
+				}
+			}
+
+			return;
+		}
+
+
+		for(int i=0;i<11;i++) {
+			ryan[i]++;
+			dfs(i,arrow+1);
+			ryan[i]--;
+		}
+
+	}
+}

Basic_Of_Algorithm/src/Today_22_06_02/coronaTest.java

@@ -0,0 +1,90 @@
+package Today_22_06_02;
+
+public class coronaTest {
+
+	public static void main(String[] args) {
+
+		String[][]places = {{"POOOP", "OXXOX", "OPXPX", "OOXOX", "POXXP"}, {"POOPX", "OXPXP", "PXXXO", "OXXXO", "OOOPP"}, {"PXOPX", "OXOXP", "OXPOX", "OXXOP", "PXPOX"}, {"OOOXX", "XOOOX", "OOOXX", "OXOOX", "OOOOO"}, {"PXPXP", "XPXPX", "PXPXP", "XPXPX", "PXPXP"}};
+		int []result = new int[places.length];
+
+		for(int i=0;i<places.length;i++) {
+
+			char[][]map = new char[places[0].length][places[0][0].length()];
+
+			for(int j=0;j<places[i].length;j++) {
+				for(int k=0;k<places[j].length;k++) {
+					map[j][k] = places[i][j].charAt(k);
+				}
+			}
+
+			result[i] = check(map);
+		}
+
+		for(int i : result)System.out.println(i);
+
+
+	}
+
+	static boolean isRight(char[][]map,int i,int j) {
+
+		//상하좌우
+		int [][] move1 = {{-1,0},{1,0},{-1,0},{0,1}};
+
+		for(int d=0;d<4;d++) {
+			int newI = i + move1[d][0];
+			int newJ = j + move1[d][1];
+
+			if(newI<0||newJ<0||map.length-1<newI||map[0].length-1<newJ) continue;
+
+			if(map[newI][newJ]=='P') return false;
+
+		}
+		//대각선
+		int [][] move2 = {{1,1},{-1,1},{1,-1},{-1,-1}};
+
+		for(int d=0;d<4;d++) {
+			int newI = i + move2[d][0];
+			int newJ = j + move2[d][1];
+
+			if(newI<0||newJ<0||map.length-1<newI||map[0].length-1<newJ) continue;
+
+			if(map[newI][newJ]=='P') {
+				if(!(map[newI][j]=='X' && map[i][newJ]=='X')) return false;
+			}
+		}
+		//맨해튼
+		int [][] move3 = {{-2,0},{2,0},{0,-2},{0,2}};
+
+		for(int d=0;d<4;d++) {
+			int newI = i + move3[d][0];
+			int newJ = j + move3[d][1];
+
+			if(newI<0||newJ<0||map.length-1<newI||map[0].length-1<newJ) continue;
+			if(map[newI][newJ]=='P') {
+				if(map[(newI+i)/2][(newJ+j)/2]!='X') return false;
+			}
+		}
+
+		return true;
+	}
+
+	static int check(char[][]map) {
+
+		for(int i=0;i<map.length;i++) {
+			for(int j=0;j<map[0].length;j++) {
+				if(map[i][j]=='P') {
+					if(!isRight(map,i,j)) {
+						return 0;
+					}
+				}
+			}
+		}
+
+
+
+		return 1;
+
+
+	}
+
+}

Basic_Of_Algorithm/src/Today_22_06_02/delivery.java

@@ -0,0 +1,80 @@
+package Today_22_06_02;
+
+import java.util.Queue;
+import java.util.LinkedList;
+
+public class delivery {
+
+	public static void main(String[] args) {
+
+
+		int INF = 50001;
+		int n = 4;
+
+		int[][]road = {{1,2,1},{1,3,5},{2,3,1},{2,4,2}};
+		int k = 2;
+		int answer = 0;
+
+		int [][] map = new int[n+1][n+1];
+
+		for(int i = 1 ; i <=n; i++) {
+			for(int j=1; j<=n ; j++) {
+				if(i==j) continue;
+				map[i][j] = INF; //무한대
+			}
+		}
+
+
+		for(int i=0;i<road.length;i++) {
+			int a = road[i][0];
+			int b = road[i][1];
+			int w = road[i][2];
+			//무한대 보다 작으면 간선의 정보 저장
+			if(map[a][b] > w) {
+				map[a][b] = w;
+				map[b][a] = w;
+			}
+
+		}
+
+		int [] dist = new int[n+1];
+		for(int i = 2; i <= n ; i++) {
+			dist[i] = INF;
+		}
+
+		boolean[] visited = new boolean[n+1];
+		visited[1] = true;
+
+
+		for(int i=1; i <=n-1 ; i++) {
+
+			int min_idx = 1;
+			int min_value = INF;
+			for(int j=2;j<=n;j++) {
+				if(!visited[j] && dist[j]<min_value) {
+					min_value = dist[j];
+					min_idx = j;
+				}
+			}
+
+			visited[min_idx] = true;
+
+
+			for(int j = 2; j <= n ; j++) {
+				if(dist[j]>dist[min_idx] + map[min_idx][j]) {
+					dist[j] = dist[min_idx] + map[min_idx][j];
+				}
+			}
+
+		}
+
+		for(int i=1;i<=n;i++) {
+			if(dist[i]<=k) answer++;
+		}
+
+		for(int i : dist)System.out.print(i+",");
+		System.out.println();
+		System.out.println(answer);
+	}
+
+}

Basic_Of_Algorithm/src/Today_22_06_02/hanoi.java

@@ -0,0 +1,34 @@
+package Today_22_06_02;
+
+public class hanoi {
+
+	public static void main(String[] args) {
+
+		int n = 4;
+
+		int [] arr = {1,2,3};
+
+		hanoi(arr[0],arr[1],arr[2],n);
+
+
+		//n개를 옮기는 문제는 n-1로 세분화되고 다시 n-1를 위해 1를 옮기는걸 세분화 시킨다
+		// a -> b (n-1)개 옮기기
+		// b - > c (n-1)개 옮기기
+		//n ==1 마지막에 남은거 옮기기
+
+	}
+
+	static void hanoi(int from, int by, int to,int n) {
+
+		if(n==1) {
+			System.out.println(from + " - > " + to);
+			return;
+		}
+
+		hanoi(from, to, by, n-1);
+		System.out.println(from + " - > " + to);
+		hanoi(by,from,to,n-1);
+
+	}
+
+}

Basic_Of_Algorithm/src/Today_22_06_02/openChatting.java

@@ -0,0 +1,57 @@
+package Today_22_06_02;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+
+public class openChatting {
+
+
+
+	public static void main(String[] args) {
+
+		String [] record = {"Enter uid1234 Muzi", "Enter uid4567 Prodo","Leave uid1234","Enter uid1234 Prodo","Change uid4567 Ryan"};
+		ArrayList<String> answerList = new ArrayList<>();
+
+		HashMap<String,String>idMap = new HashMap<>();
+
+		for(String str : record) {
+
+			String []temp = str.split(" ");
+
+			String action = temp[0];
+			String id = temp[1];
+
+			if(action.equals("Leave")) continue;
+
+			String nick = temp[2];
+
+			idMap.put(id, nick);
+
+
+		}
+
+		for(String str : record) {
+
+			String []temp = str.split(" ");
+
+			String action = temp[0];
+			if(action.equals("Change")) continue;
+			String id = temp[1];
+			String nick = idMap.get(id);
+
+			String ans = nick+"님이 " + (action.equals("Enter") ? "들어왔습니다." : "나갔습니다.");
+
+			answerList.add(ans);
+
+		}
+
+		String[]answer = new String[answerList.size()];
+
+		for(int i=0;i<answer.length;i++) answer[i] = answerList.get(i);
+
+		for(String str  : answer)System.out.println(str);
+
+
+
+	}
+}