Answer 1

function method(arr) {
  arr = Array.from(new Set(arr.sort((a, b) => a - b)))
  const result = []
  const len = arr[arr.length - 1] / 10 + 1
  let current = 0
  for (let i = 1; i <= len; i++) {
    console.log(i)
    let min = (i - 1) * 10
    let max = 10 * i
    const temp = []
    for (let j = current; j < arr.length; j++) {
      if (arr[j] >= min && arr[j] < max) {
        temp.push(arr[j])
        if (j === arr.length - 1) {
          result.push(temp)
        }
      } else {
        if (temp.length > 0) {
          current = j
          result.push(temp)
        }
        break
      }
    }
  }
  return result
}
function randomMethod() {
  const arr = []
  arr.length = 10
  for (let i = 0; i < arr.length; i++) {
    arr[i] = Math.floor(Math.random() * 100)
  }
  return arr
}
console.log(method(randomMethod()))

Answer 2

//题目开放，变式很多了
const dateTransfer = (start, end) => {
const distance = 1000 * 60 * 60 * 24;
const startTime = new Date(start).getTime();
const endTime = new Date(end).getTime();
const result = [];

while(startTime < endTime){
    result.push(new Date(startTime + distance).toLocaleDateString().replace(///g, '-'));
    startTime +=  distance;   
}
return result;

}

dateTransfer('2019-08-01', '2019-08-30')