[PS][기출문제][삼성]/[BOJ][14503][로봇청소기]

boj14503.cpp

#include <iostream>
using namespace std;

int n, m, dir;
int map[50][50];
bool visited[50][50];
int dx[4] = { -1, 0, 1 , 0 };
int dy[4] = { 0,1,0,-1 };
int nextDir[4] = { 3,0,1,2 };
pair<int, int> curr;
int ans = 0;
bool inRange(int x, int y) {
	return 0 <= x && x < n && 0 <= y && y < m;
}

void dfs(int x, int y) {
	if (map[x][y] != 2) {
		map[x][y] = 2;
		ans++;
	}
	int k = 0;
	int nd = 0, nx = 0, ny = 0;
	for (k = 0; k < 4; k++) {
		nd = nextDir[dir];
		nx = x + dx[nd];
		ny = y + dy[nd];
		if (!inRange(nx, ny)) continue;
		if (map[nx][ny] == 0) {
			dir = nd;
			return dfs(nx, ny);
		}
		else {
			dir = nd;
			continue;
		}
	}
	if (inRange(x - dx[dir], y - dy[dir]) && 
		map[x - dx[dir]][y - dy[dir]] != 1)
		return dfs(x - dx[dir], y - dy[dir]);
	else return;
}

int main (void) {
	cin >> n >> m;
	int i = 0, j = 0;
	cin >> curr.first >> curr.second;
	cin >> dir;
	for (i = 0; i < n; i++) {
		for (j = 0; j < m; j++) {
			cin >> map[i][j];
		}
	}
	dfs(curr.first, curr.second);
	cout << ans << "\n";
	
	return 0;
}