Merge branch 'main' into 6-Me-in-U

BOJ-ios/README.md

@@ -7,4 +7,4 @@
 | 3차시 | 2024.03.26 | 펜윅트리 |                             [구간 합 구하기](https://www.acmicpc.net/problem/2042)                             | [#13](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pulls/13) |
 | 4차시 | 2024.03.30 | 볼록껍질 |                               [볼록 껍질](https://www.acmicpc.net/problem/1708)                                | [#14](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pulls/14) |
 | 5차시 | 2024.04.29 |  스위핑  |                    [여러 직사각형의 전체 면적 구하기](https://www.acmicpc.net/problem/2672)                    | [#19](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pulls/19) |
-| 6차시 | 2024.05.13 | 위상정렬 |                               [줄 세우기](https://www.acmicpc.net/problem/2252)                                | [#20](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pulls/20) |
+| 6차시 | 2024.05.13 | 위상정렬 |                               [줄 세우기](https://www.acmicpc.net/problem/2252)                                | [#20](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pulls/20) |

BOJ-ios/스위핑/P2672번_여러_직사각형의_전체_면적_구하기/Main.java

@@ -0,0 +1,84 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+import java.util.StringTokenizer;
+
+public class Main {
+    static class RectangleEvent implements Comparable<RectangleEvent> {
+        int x;
+        int yUp;
+        int yDown;
+        int chk;
+
+        public RectangleEvent(int x, int yDown, int yUp, int chk) {
+            this.x = x;
+            this.yUp = yUp;
+            this.yDown = yDown;
+            this.chk = chk;
+        }
+
+        @Override
+        public int compareTo(RectangleEvent o) {
+            if (this.x == o.x)
+                return this.chk - o.chk;
+            return this.x - o.x;
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            if (this == obj) {
+                return true;
+            }
+            if (obj == null || getClass() != obj.getClass()) {
+                return false;
+            }
+            RectangleEvent that = (RectangleEvent) obj;
+            return this.x == that.x && this.yUp == that.yUp && this.yDown == that.yDown && this.chk == that.chk;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(x, yUp, yDown, chk);
+        }
+    }
+
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = null;
+        int n = Integer.parseInt(br.readLine());
+        List<RectangleEvent> events = new ArrayList<>();
+        int[] sweep = new int[20001];
+        while (n-- > 0) {
+            st = new StringTokenizer(br.readLine());
+            int xStart = (int) (Double.parseDouble(st.nextToken()) * 10);
+            int yDown = (int) (Double.parseDouble(st.nextToken()) * 10);
+            int xEnd = xStart + (int) (Double.parseDouble(st.nextToken()) * 10);
+            int height = (int) (Double.parseDouble(st.nextToken()) * 10);
+            int yUp = yDown + height;
+            events.add(new RectangleEvent(xStart, yDown, yUp, 1));
+            events.add(new RectangleEvent(xEnd, yDown, yUp, -1));
+        }
+        Collections.sort(events);
+        int area = 0;
+        int x = 0;
+        for (RectangleEvent event : events) {
+            int count = 0;
+            for (int i = 0; i < 20001; i++)
+                if (sweep[i] > 0)
+                    count++;
+            area += count * (event.x - x);
+            for (int i = event.yDown; i < event.yUp; i++) {
+                if (event.chk == 1)
+                    sweep[i]++;
+                else
+                    sweep[i]--;
+            }
+            x = event.x;
+        }
+        System.out.println(area % 100 == 0 ? (int) (area * 0.01) : String.format("%.2f", area * 0.01));
+    }
+}

SunYerim/README.md

@@ -1,7 +1,8 @@
 ## ✏️ 기록   
 
-| 차시  |     날짜     | 문제유형 |                       링크                        |                            풀이                            |
-|:---:|:----------:|:----:|:-----------------------------------------------:|:--------------------------------------------------------:|
+| 차시  |     날짜     | 문제유형 |                         링크                          |                            풀이                            |
+|:---:|:----------:|:----:|:---------------------------------------------------:|:--------------------------------------------------------:|
 | 1차시 | 2024.03.18 |  구현  | [이차원 배열과 연산](https://www.acmicpc.net/problem/17140) | [#1](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/5)  |
-| 2차시 | 2024.03.22 |  스택  |   [키로거](https://www.acmicpc.net/problem/5397)   | [#2](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/7)  |
-| 3차시 | 2024.03.26 |  DP  |    [앱](https://www.acmicpc.net/problem/7579)    | [#3](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/11) |
+| 2차시 | 2024.03.22 |  스택  |     [키로거](https://www.acmicpc.net/problem/5397)     | [#2](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/7)  |
+| 3차시 | 2024.03.26 |  DP  |      [앱](https://www.acmicpc.net/problem/7579)      | [#3](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/11) |
+| 4차시 | 2024.03.30 | 그래프  |     [탈출](https://www.acmicpc.net/problem/3055)      | [#4](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/16) |

SunYerim/그래프/BOJ3055.java

@@ -0,0 +1,123 @@
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.Queue;
+import java.util.StringTokenizer;
+
+public class BOJ3055 {
+    static int r, c;
+    static int startX, startY, endX, endY;
+    static char[][] map;
+    static boolean[][] visited;
+    static boolean[][] waterVisited;
+    static int[] dx = {1, -1, 0, 0};
+    static int[] dy = {0, 0, -1, 1};
+    static ArrayDeque<Node> water;
+    public static void main(String[] args) throws IOException {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        StringTokenizer st = new StringTokenizer(br.readLine());
+        r = Integer.parseInt(st.nextToken());
+        c = Integer.parseInt(st.nextToken());
+        map = new char[r][c];
+        visited = new boolean[r][c];
+        waterVisited = new boolean[r][c];
+        water = new ArrayDeque<Node>();
+
+        for (int i = 0; i < r; i++) {
+            String tmp = br.readLine();
+            for (int j = 0; j < c; j++) {
+                map[i][j] = tmp.charAt(j);
+                if (map[i][j] == 'S') {
+                    startX = i;
+                    startY = j;
+                } else if (map[i][j] == 'D') {
+                    endX = i;
+                    endY = j;
+                } else if (map[i][j] == '*') {
+                    water.add(new Node(i, j, 0));
+                }
+            }
+        }
+
+        bfs(startX, startY);
+    }
+
+    private static void bfs(int x, int y) {
+        Queue<Node> queue = new ArrayDeque<>(); // 두더지가 가는 경로만 담는다
+        queue.add(new Node(x, y, 0)); // 출발지점 넣고
+        visited[x][y] = true;
+
+        while (!queue.isEmpty()) {
+            // 물을 퍼뜨린 후 고슴도치 이동 -> 고슴도치도 물은 통과 못한다.
+            int size = queue.size();
+            for (int s = 0; s < size; s++) {
+                Node curr = queue.poll();
+                int currX = curr.x;
+                int currY = curr.y;
+                int currCnt = curr.count;
+                if (map[currX][currY] == '*')
+                    continue;
+
+                // 기저
+                if (map[currX][currY] == 'D') {
+                    System.out.println(currCnt);
+                    return;
+                }
+                for (int i = 0; i < 4; i++) {
+                    int nx = dx[i] + currX;
+                    int ny = dy[i] + currY;
+                    if (nx >= 0 && ny >= 0 && nx < r && ny < c && !visited[nx][ny]) {
+                        // 고슴도치가 가려는 자리에 물이나 돌이 있으면
+                        if (map[nx][ny] == '*' || map[nx][ny] == 'X') continue;
+                        visited[nx][ny] = true;
+
+                        queue.add(new Node(nx, ny, currCnt+1));
+
+                    }
+                }
+
+            }
+            // 우선 물부터 퍼뜨린다. -> 물은 돌과 소굴이 있는 자리, D로는 퍼질 수 없다.
+            int waterSize = water.size();
+            for (int i = 0; i < waterSize; i++) {
+                Node waters = water.poll();
+                int waterX = waters.x;
+                int waterY = waters.y;
+                //int waterCnt = waters.count;
+                // 가려는 곳이 돌이 아니고 비버의 굴이 아닐때
+                for (int j = 0; j < 4; j++) {
+                    int nx = dx[j] + waterX;
+                    int ny = dy[j] + waterY;
+                    if (nx >= 0 && ny >= 0 && nx < r && ny < c) {
+                        // 돌이아니고 굴이 아니여야함
+                        if (map[nx][ny] == 'X' || map[nx][ny] == 'D' || waterVisited[nx][ny]) continue;
+                        // 갈 수 있는 곳이라면
+
+                        map[nx][ny] = '*';
+                        waterVisited[nx][ny] = true;
+                        water.add(new Node(nx, ny, 0));
+
+
+                    }
+                }
+            }
+        }
+
+        System.out.println("KAKTUS");
+
+
+
+
+    }
+
+    static class Node {
+        private int x, y, count;
+        public Node (int x, int y, int count) {
+            this.x = x;
+            this.y = y;
+            this.count = count;
+        }
+    }
+}

erase-jeong/BFS/BOJ2178_미로탐색.py

@@ -0,0 +1,38 @@
+from collections import deque
+
+N, M = map(int, input().split())
+
+graph = []
+
+for _ in range(N):
+    graph.append(list(map(int, input())))
+
+def BFS(x, y):
+    # 이동할 상, 하, 좌, 우 방향 정의
+    dx = [-1,1,0,0]
+    dy = [0,0,-1,1]
+
+    queue = deque()
+    queue.append((x,y))
+
+    while queue:
+        x, y = queue.popleft()
+
+        for i in range(4):
+            nx = x + dx[i]
+            ny = y + dy[i]
+
+            if nx<0 or nx>=N or ny<0 or ny>=M:
+                continue
+
+            if graph[nx][ny]==0:
+                continue
+
+            if graph[nx][ny]==1:
+                graph[nx][ny] = graph[x][y]+1
+                queue.append((nx,ny))
+
+
+    return graph[N-1][M-1]
+
+print(BFS(0,0))

erase-jeong/DFS_BFS/촌수계산.py

@@ -0,0 +1,35 @@
+#입력값 받는 부분
+n=int(input())
+a,b=map(int,input().split())
+m=int(input())
+
+#기본 선언
+graph=[[] for _ in range(n+1)]  #노드의 번호와 배열 번호 통일시키기 위해서 n이 아닌 n+1 사용
+visited=[[False]*(n+1)]
+result=[]
+
+
+for _ in range(m):
+    x,y=map(int, input().split())
+    graph[x].append(y)
+    graph[y].append(x)
+
+
+
+def dfs(v,num):
+    num+=1
+    visited[v]=True
+
+    if v==b:
+        result.append(num)
+
+    for i in graph[v]:
+        if not visited[i]:
+            dfs(i,num)
+
+dfs(a,0)
+
+if len(result)==0:
+    print(-1)
+else:
+    print(result)

erase-jeong/README.md

@@ -2,5 +2,7 @@
 
 | 차시 |    날짜    | 문제유형 | 링크 | 풀이 |
 |:----:|:---------:|:----:|:-----:|:----:|
-| 1차시 | 2024.03.18 |  그리디  | [구명보트](https://school.programmers.co.kr/learn/courses/30/lessons/42885)  | [#1](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/4) |
----
+| 1차시 | 2023.03.18 |  그리디  |  [구명보트](https://school.programmers.co.kr/learn/courses/30/lessons/42885)  | [#1](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/4)|
+| 2차시 | 2023.03.23 |  DFS/BFS  |  [촌수계산](https://www.acmicpc.net/problem/2644)  | [#2](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/8)|
+| 3차시 | 2023.03.28 |  DP  |  [평범한 배낭](https://www.acmicpc.net/problem/12865)  | [#3](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/12)|
+| 4차시 | 2023.03.28 |  DP  |  [미로 탐색](https://www.acmicpc.net/problem/2178)  | [#4](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/17)|

wjdheesp44/README.md

@@ -5,4 +5,5 @@
 | 1차시 | 2024.03.18 |  구현  | [주사위 굴리기](https://www.acmicpc.net/problem/14499)  | [#3](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/3) |
 | 2차시 | 2024.03.22 |  구현  | [뱀](https://www.acmicpc.net/problem/3190)  | [#6](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/6) |
 | 3차시 | 2024.03.26 |  백트래킹  | [연산자 끼워넣기](https://www.acmicpc.net/problem/14888)  | [#10](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/10) |
+| 4차시 | 2024.03.30 |  bfs  | [안전 영역](https://www.acmicpc.net/problem/2468)  | [#15](https://github.com/AlgoLeadMe/AlgoLeadMe-9/pull/15) |
 ---

wjdheesp44/bfs/2468_안전 영역.py

@@ -0,0 +1,38 @@
+import sys
+from collections import deque
+input = sys.stdin.readline
+
+sum = 0
+cnt = 0
+n = int(input())
+max_height = 0
+board = [list(map(int, input().split())) for _ in range(n)]
+
+max_height = max(map(max, board))
+
+def bfs(x, y, k):
+    dx, dy = [-1, 0, 1, 0], [0, 1, 0, -1]
+    q = deque()
+    q.append((x, y))
+
+    while q:
+        x, y = q.popleft()
+        for i in range(4):
+            nx, ny = x + dx[i], y + dy[i]
+            if 0 <= nx < n and 0 <= ny < n and visited[nx][ny] == 0 and board[nx][ny] > k:
+                visited[nx][ny] = 1
+                q.append((nx, ny))
+
+
+for k in range(max_height):
+    visited = [[0] * n for _ in range(n)]
+    cnt = 0
+
+    for i in range(n):
+        for j in range(n):
+            if visited[i][j] == 0 and board[i][j] > k:
+                bfs(i, j, k)
+                cnt += 1
+    sum = max(sum, cnt)
+
+print(sum)