BaekJoon 14503, 로봇 청소기

제가 dfs를 사용하는 것에 맛들렸을 때 풀었던 문제들이라 dfs를 엄청 남발하면서

삼성 문제들을 풀었던 것 같습니다.

https://www.acmicpc.net/problem/14503

문제는 위 링크에서의 조건에 맞도록 로봇청소기의 이동 경로를 생각하면 되는 간단한 문제입니다.

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import java.util.Scanner; public class BaekJoon14503 { static int N, M, r, c, d, count; static int[][] table; static Point current; static boolean isOperate = true; final static int NORTH = 0, EAST = 1, SOUTH = 2, WEST = 3; public static void main(String[] args) { Scanner sc = new Scanner(System.in); N = sc.nextInt();M = sc.nextInt(); r = sc.nextInt(); c = sc.nextInt(); current = new Point(r, c);count = 0; d = sc.nextInt();table = new int[N][M]; for (int i = 0; i < N; i++) { for (int j = 0; j < M; j++) { table[i][j] = sc.nextInt(); } } dfs(current); System.out.println(count); } public static void dfs(Point p) { if (table[p.x][p.y] == 0)count++; table[p.x][p.y] = -1; boolean isMove = false; int idx = 0; while (idx++ < 4) { switch (d) { case NORTH:d = WEST; if (table[p.x][p.y - 1] == 0) { isMove = true;dfs(new Point(p.x, p.y - 1)); }break; case EAST:d = NORTH; if (table[p.x - 1][p.y] == 0) { isMove = true;dfs(new Point(p.x - 1, p.y)); }break; case SOUTH:d = EAST; if (table[p.x][p.y + 1] == 0) { isMove = true;dfs(new Point(p.x, p.y + 1)); }break; case WEST:d = SOUTH; if (table[p.x + 1][p.y] == 0) { isMove = true;dfs(new Point(p.x + 1, p.y)); }break; }if (isMove) break; } if (!isMove) { switch (d) { case NORTH: if (table[p.x + 1][p.y] == 1) isOperate = false; else dfs(new Point(p.x + 1, p.y));break; case EAST: if (table[p.x][p.y - 1] == 1) isOperate = false; else dfs(new Point(p.x, p.y - 1));break; case SOUTH: if (table[p.x - 1][p.y] == 1) isOperate = false; else dfs(new Point(p.x - 1, p.y));break; case WEST: if (table[p.x][p.y + 1] == 1) isOperate = false; else dfs(new Point(p.x, p.y + 1));break; } } if (!isOperate) return; } }