生成随机学号

test

const grade = [9, 10, 11, 12];
const sequence = [];
for (let i = 0; i <= 30; i++) {
  sequence.push(i);
}

const generate = (arr) => {
  const obj = {};
  for (item of arr)
    if (item < 100) {
      const l = item % 10;
      const hStr = Math.floor(item / 10).toString();
      if (!obj.hasOwnProperty(hStr)) {
        obj[hStr] = [];
      }
      obj[hStr].push(l);
    }
  return obj;
};

const Lobj = { grade: generate(grade), sequence: generate(sequence) };

const getResult = (obj) => {
  let keysArr = Object.keys(obj);
  let result = {};
  result.high = keysArr[Math.floor(Math.random() * keysArr.length)];
  result.low =
    obj[result.high][Math.floor(Math.random() * obj[result.high].length)];
  return result.high + result.low;
};

console.log(getResult(Lobj.grade) + "-" + getResult(Lobj.sequence));