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function solution(n, edges) {
  const connectedList = getConnectedList(n, edges);
  const isVistied = new Array(n + 1).fill(false);
  const minDistance = new Array(n + 1).fill(Number.MAX_SAFE_INTEGER);
  const queue = new Array();

  queue.push(1);
  minDistance[0] = 0;
  minDistance[1] = 0;
  isVistied[1] = true;
  while (queue.length) {
    const from = queue.pop();
    connectedList[from].forEach((to) => {
      if (!isVistied[to]) {
        queue.push(to);
        isVistied[to] = true;
      }

      minDistance[to] =
        minDistance[to] > minDistance[from] + 1
          ? minDistance[from] + 1
          : minDistance[to];
    });
  }
  const max = Math.max(...minDistance);
  const answer = minDistance.filter((d) => d === max);

  return answer.length;
}

function getConnectedList(n, edges) {
  const connectedList = new Array(n + 1).fill(0).map((x) => new Array(0));

  edges.forEach((edge) => {
    connectedList[edge[0]].push(edge[1]);
    connectedList[edge[1]].push(edge[0]);
  });
  return connectedList;
}