32-kangrae-jo

kangrae-jo/BFS/32-kangrae-jo.cpp

@@ -0,0 +1,164 @@
+#include <unordered_map>
+#include <vector>
+#include <queue>
+#include <algorithm>
+
+using namespace std;
+
+const int EMPTY = 0;
+const int BLOCK = 1;
+const int OFFSET[4][2] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};
+
+int N, id = 2;
+
+// 조각 번호 -> 블럭을 이루는 모든 {y,x} * rotate 4개
+unordered_map<int, unordered_map<int, vector<pair<int,int>>>> um; 
+vector<vector<pair<int, int>>> emptys;
+
+bool isIn(int y, int x) { return 0 <= y && y < N && 0 <= x && x < N; }
+
+vector<vector<int>> rotate(vector<vector<int>>& table) {
+    vector<vector<int>> rotated(N, vector<int>(N));
+    for (int y = 0; y < N; y++) {
+        for (int x = 0; x < N; x++) {
+            rotated[x][N - 1 - y] = table[y][x];
+        }
+    }
+    return rotated;
+}
+
+void checkBlock(vector<vector<int>>& table, int y, int x, int id, int rot, int target, vector<vector<bool>>& visited) {
+    queue<pair<int, int>> q;
+    q.push({y, x});
+    visited[y][x] = true;
+
+    while (!q.empty()) {
+        auto[curY, curX] = q.front();
+        q.pop();
+
+        um[id][rot].push_back({curY - y, curX - x});
+
+        for (int dir = 0; dir < 4; dir++) {
+            int nextY = curY + OFFSET[dir][0];
+            int nextX = curX + OFFSET[dir][1];
+            if (isIn(nextY, nextX) && table[nextY][nextX] == target && !visited[nextY][nextX]) {
+                q.push({nextY, nextX});
+                visited[nextY][nextX] = true;
+            }
+        }
+    }
+    sort(um[id][rot].begin(), um[id][rot].end());
+}
+
+void checkBlock(vector<vector<int>>& table, int y, int x, int id, int rot) {
+    queue<pair<int, int>> q;
+    q.push({y, x});
+    table[y][x] = id;
+
+    while (!q.empty()) {
+        auto[curY, curX] = q.front();
+        q.pop();
+
+        um[id][rot].push_back({curY - y, curX - x});
+
+        for (int dir = 0; dir < 4; dir++) {
+            int nextY = curY + OFFSET[dir][0];
+            int nextX = curX + OFFSET[dir][1];
+            if (isIn(nextY, nextX) && table[nextY][nextX] == BLOCK) {
+                q.push({nextY, nextX});
+                table[nextY][nextX] = id;
+            }
+        }
+    }
+    sort(um[id][rot].begin(), um[id][rot].end());
+}
+
+void makeBlocks(vector<vector<int>>& table, int rot) {    
+    for (int y = 0; y < N; y++) {
+        for (int x = 0; x < N; x++) {
+            if (table[y][x] == BLOCK) {
+                checkBlock(table, y, x, id, rot);
+                id++;
+            }
+        }
+    }
+}
+
+void makeBlocks_(vector<vector<int>>& table, int rot) {
+    vector<vector<bool>> visited(N, vector<bool>(N, false));
+    for (int y = 0; y < N; y++) {
+        for (int x = 0; x < N; x++) {
+            if (table[y][x] >= 2 && !visited[y][x]) {
+                checkBlock(table, y, x, table[y][x], rot, table[y][x], visited);
+            }
+        }
+    }
+}
+
+void checkEmpty(vector<vector<int>>& board, int y, int x) {
+    queue<pair<int, int>> q;
+    q.push({y, x});
+    board[y][x]++; 
+
+    vector<pair<int, int>> temp;
+    while (!q.empty()) {
+        auto[curY, curX] = q.front();
+        q.pop();
+
+        temp.push_back({curY - y, curX - x});
+
+        for (int dir = 0; dir < 4; dir++) {
+            int nextY = curY + OFFSET[dir][0];
+            int nextX = curX + OFFSET[dir][1];
+            if (isIn(nextY, nextX) && board[nextY][nextX] == EMPTY) {
+                q.push({nextY, nextX});
+                board[nextY][nextX]++; 
+            }
+        }
+    }
+    sort(temp.begin(), temp.end());
+    emptys.push_back(temp);
+}
+
+void makeEmptys(vector<vector<int>>& board) {    
+    for (int y = 0; y < N; y++) {
+        for (int x = 0; x < N; x++) {
+            if (board[y][x] == EMPTY) {
+                checkEmpty(board, y, x);
+            }
+        }
+    }
+}
+
+int solution(vector<vector<int>> board, vector<vector<int>> table) {
+    N = board.size();
+
+    makeBlocks(table, 0);
+    for (int rot = 1; rot < 4; rot++) {
+        table = rotate(table);
+        makeBlocks_(table, rot);
+    }
+
+    makeEmptys(board);
+
+    int answer = 0;
+    unordered_map<int, bool> used;
+
+    for (vector<pair<int, int>>& empty : emptys) {
+        bool flag = false;
+        for (int i = 2; i < id; i++) {
+            if (used[i]) continue;
+            for (int rot = 0; rot < 4; rot++) {
+                if (empty == um[i][rot]) {
+                    answer += empty.size();
+                    used[i] = true;
+                    flag = true;
+                    break;
+                }
+            }
+            if (flag) break; 
+        }
+    }
+
+    return answer;
+}

kangrae-jo/README.md

@@ -32,4 +32,5 @@
 | 28차시 | 2024.06.10 |  BFS  | [경주로 건설](https://school.programmers.co.kr/learn/courses/30/lessons/67259)|[#110](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/110)|
 | 29차시 | 2024.06.19 |  TRIE  | [[3차] 자동완성](https://school.programmers.co.kr/learn/courses/30/lessons/17685)|[#114](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/114)|
 | 30차시 | 2024.07.18 |  BFS  | [치즈](https://www.acmicpc.net/problem/2638)|[#117](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/117)|
-| 31차시 | 2024.07.31 |  Prefix Sum  | [두 배열의 합](https://www.acmicpc.net/problem/2143)|[#122](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/122)|
+| 31차시 | 2024.07.31 |  Prefix Sum  | [두 배열의 합](https://www.acmicpc.net/problem/2143)|[#122](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/122)|
+| 32차시 | 2024.08.10 |  BFS  | [퍼즐 조각 채우기](https://school.programmers.co.kr/learn/courses/30/lessons/84021)|[#130](https://github.com/AlgoLeadMe/AlgoLeadMe-12/pull/130)|