[백준 20057] 마법사 상어와 토네이도 - 시뮬레이션

Author: HiiWee

hoseok/week34/Boj20057.java

@@ -0,0 +1,94 @@
+import java.io.*;
+import java.util.*;
+
+class Main {
+
+    // 좌 하 우 상
+    private static final int[] rows = {0, 1, 0, -1};
+    private static final int[] cols = {-1, 0, 1, 0};
+    private static final int[][][] dustRows = {
+            {{-2, 0, 2}, {-1, -1, 10}, {-1, 0, 7}, {-1, 1, 1}, {0, -2, 5}, {1, -1, 10}, {1, 0, 7}, {1, 1, 1}, {2, 0, 2}},
+            {{-1, -1, 1}, {-1, 1, 1}, {0, -2, 2}, {0, -1, 7}, {0, 1, 7}, {0, 2, 2}, {1, -1, 10}, {1, 1, 10}, {2, 0, 5}},
+            {{-2, 0, 2}, {-1, -1, 1}, {-1, 0, 7}, {-1, 1, 10}, {0, 2, 5}, {1, -1, 1}, {1, 0, 7}, {1, 1, 10}, {2, 0, 2}},
+            {{-2, 0, 5}, {-1, -1, 10}, {-1, 1, 10}, {0, -2, 2}, {0, -1, 7}, {0, 1, 7}, {0, 2, 2}, {1, -1, 1}, {1, 1, 1}}
+    };
+
+    private static int n, totalOutDust;
+    private static int[][] map;
+
+    public static void main(String[] args) throws Exception {
+        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
+        n = Integer.parseInt(br.readLine());
+        map = new int[n][n];
+
+        for (int i = 0; i < n; i++) {
+            StringTokenizer st = new StringTokenizer(br.readLine());
+            for (int j = 0; j < n; j++) {
+                map[i][j] = Integer.parseInt(st.nextToken());
+            }
+        }
+
+        int moveAmount = 1;
+        int currentMoveAmount = 0;
+        int directionCount = 0;
+        int direction = 0;
+        int nextR = n / 2;
+        int nextC = n / 2;
+
+        for (int count = 0; count < n * n - 1; count++) {
+            nextR += rows[direction];
+            nextC += cols[direction];
+            // a의 위치
+            int aRow = nextR + rows[direction];
+            int aCol = nextC + cols[direction];
+
+            moveDust(direction, nextR, nextC, aRow, aCol);
+            // 현재 방향으로 얼마나 이동했는지
+            currentMoveAmount++;
+            // 현재 방향으로 꽉 채워서 이동했다면
+            if (currentMoveAmount == moveAmount) {
+                // 다음 위치로 이동하도록 변경
+                directionCount++;
+                direction = (direction + 1) % 4;
+                currentMoveAmount = 0;
+            }
+            // 방향 전환이 두 번 됐다면 현재 방향 이동량을 1증가
+            if (directionCount == 2) {
+                moveAmount++;
+                directionCount = 0;
+            }
+
+        }
+
+        bw.write(totalOutDust + "");
+        bw.flush();
+        bw.close();
+    }
+
+    public static void moveDust(int direction, int r, int c, int aRow, int aCol) {
+        int currentDust = map[r][c];
+        int totalMoveDust = 0;
+        for (int i = 0; i < 9; i++) {
+            int nextR = r + dustRows[direction][i][0];
+            int nextC = c + dustRows[direction][i][1];
+            int percentage = dustRows[direction][i][2];
+            int moveDust = (int) (currentDust * (percentage / 100.0));
+            totalMoveDust += moveDust;
+
+            // 모래가 밖을 벗어나는 위치라면
+            if (nextR < 0 || nextR >= n || nextC < 0 || nextC >= n) {
+                totalOutDust += moveDust;
+                continue;
+            }
+            map[nextR][nextC] += moveDust;
+        }
+        if (aRow < 0 || aRow >= n || aCol < 0 || aCol >= n) {
+            // a의 위치가 맵 밖을 벗어나면
+            totalOutDust += currentDust - totalMoveDust;
+        } else {
+            map[aRow][aCol] += currentDust - totalMoveDust;
+        }
+        map[r][c] = 0;
+    }
+}