[백준 BoJ] 2206 - 벽 부수고 이동하기

// https://www.acmicpc.net/problem/2206
// 벽 부수고 이동하기
#include<iostream>
#include<string>
#include<queue>
using namespace std;
int N, M;
int map[1002][1002];
int visited[1002][1002][2];
int dx[] = { 1,-1,0,0 };
int dy[] = { 0,0,1,-1 };

queue<pair<pair<int, int>, int>> q;

int bfs() {
	visited[1][1][1] = 1;
	q.push({{ 1,1 }, 1});

	while (!q.empty()) {
		int x = q.front().first.first;
		int y = q.front().first.second;
		int b = q.front().second;

		q.pop();

		if (x == N && y == M) return visited[x][y][b];

		for (int i = 0; i < 4; i++) {
			int nx = x + dx[i];
			int ny = y + dy[i];

			if (nx <= 0 || ny <= 0 || nx > N || ny > M) continue;

			if (map[nx][ny] == 1 && b == 1) {
				visited[nx][ny][b - 1] = visited[x][y][b] + 1;
				q.push({ {nx, ny}, b - 1 });
			}
			else if (map[nx][ny]==0 && visited[nx][ny][b]==0) {
				visited[nx][ny][b] = visited[x][y][b] + 1;
				q.push({ {nx,ny}, b });
			}
		}

	}
	return -1;
}
int main() {
	ios::sync_with_stdio(false);
	cin.tie(NULL); cout.tie(NULL);

	cin >> N >> M;

	for (int i = 1; i <= N; i++) {
		string s;
		cin >> s;
		for (int j = 1; j <= s.size(); j++) {
			map[i][j] = s[j-1] - '0';
		}
	}


	int ans = bfs();
	cout << ans;

}

• BFS