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export default function validPath(    n: number,    edges: number[][],    source: number,    destination: number,): boolean {    if (source === destination) return true;    if (edges.length === 0) return false;    const nodes = new Set(Array(n).keys());    const edge: Set<number>[] = Array(n)        .fill(0)        .map(() => new Set());    for (const [a, b] of edges) {        edge[a].add(b);        edge[b].add(a);    }    if (!nodes.has(destination) || !nodes.has(source)) return false;
    let current = new Set([source]);
    let rightcurrent = new Set([destination]);    nodes.delete(destination);    nodes.delete(source);    //  let step = 1;    while (current.size) {        if (current.size > rightcurrent.size) {            [current, rightcurrent] = [rightcurrent, current];        }
        const temp: Set<number> = new Set();
        for (const word of current) {            for (const right of rightcurrent) {                if (edge[word].has(right)) {                    return true;                }            }            for (const other of nodes) {                if (edge[other].has(word)) {                    temp.add(other);
                    nodes.delete(other);                }            }        }
        if (temp.size === 0) return false;        current = temp;        //  step = step + 1;    }
    return false;}