题解 | #走迷宫#

求助，为什么栽在最后一题

const rl = require("readline").createInterface({ input: process.stdin });
var iter = rl[Symbol.asyncIterator]();
const readline = async () => (await iter.next()).value;

void (async function () {
    // Write your code here
    /**
     * 无权重
     * 一个点第一次到的时候一定是最短路径
     */
    let arr = [];

    let [height, width] = (await readline()).split(" ");
    let [x1, y1, x2, y2] = (await readline()).split(" ");
    while ((line = await readline())) {
        arr.push(line);
    }

    let cur = [x1 - 1, y1 - 1];
    let pre = [x2 - 1, y2 - 1];

    let arr2 = Array.from({ length: height }, () => {
        return Array.from({ length: width }, () => 0);
    });

    const queue = [];
    const visited = new Set();
    let bool = false;

    const bfs = () => {
        while (queue.length && !bool) {
            const [x, y] = queue.shift();
            [
                [x - 1, y],
                [x + 1, y],
                [x, y - 1],
                [x, y + 1],
            ].forEach((item) => {
                const [itemX, itemY] = item;

                if (
                    !visited.has(item.join("")) &&
                    arr[itemX]?.[itemY] === "."
                ) {
                    queue.push(item);
                    visited.add(item.join(""));
                    arr2[itemX][itemY] = [x, y];

                    if (item.join("") === pre.join("")) bool = true;
                }
            });
        }
    };
    let stack = [];
    const fromTo = (from, to) => {
        if (arr[to[0]][to[1]] === "*") {
            return;
        } else {
            visited.add(from.join(""));
            queue.push(from);
            bfs();
            let [x, y] = to;
            while (arr2[x][y]) {
                stack.push(`${x}${y}`);
                [x, y] = arr2[x][y];
            }
        }
    };

    fromTo(cur, pre);

    console.log(stack.length ? stack.length : -1);
})();