核心内容

1. 将ip逐点转为8位
2. 将转换之后的ip 转为整数，如果显示为负数，二进制取反后parseInt(ip,2)
3. 注意ip与mask的判定，mask的二进制中只要包含(01)就是不合法的

let lines = [];
const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
});
rl.on("line", function (line) {
  lines.push(line);
  if (lines.length == 3) {
    let mask = ip2bin(lines[0]);
    let ip1 = ip2bin(lines[1]);
    let ip2 = ip2bin(lines[2]);

    if (mask && ip1 && ip2) {
      //             let a = "0b1000001110000101100101000001111"
      //             let b = "0b11101000001010110000011100111011"
      //             console.log(a&b)
      if (mask.includes("01")) {
        console.log("1");
      } else {
        if (
          ~(parseInt(ip1, 2) & parseInt(mask, 2)) ==
          ~(parseInt(ip2, 2) & parseInt(mask, 2))
        ) {
          console.log("0");
        } else {
          console.log("2");
        }
      }
    }
    lines = [];
  }
});

function ip2bin(ip) {
  // 分割
  let ipArr = ip.split(".");
  let ipOut = "";
  for (let value of ipArr) {
    if (+value > 255 || +value < 0) {
      console.log("1");
      return false;
    }
    let dec = parseInt(value);
    let bin = dec.toString(2).padStart(8, 0);
    ipOut = ipOut + bin;
  }
  return ipOut;
}