Human readable duration format

4 kyu

題目描述

Description

Your task in order to complete this Kata is to write a function which formats a duration, given as a number of seconds, in a human-friendly way.

The function must accept a non-negative integer. If it is zero, it just returns "now". Otherwise, the duration is expressed as a combination of years, days, hours, minutes and seconds.

It is much easier to understand with an example:

• For seconds = 62, your function should return "1 minute and 2 seconds"
• For seconds = 3662, your function should return "1 hour, 1 minute and 2 seconds" For the purpose of this Kata, a year is 365 days and a day is 24 hours.

Note that spaces are important.

Detailed rules The resulting expression is made of components like 4 seconds, 1 year, etc. In general, a positive integer and one of the valid units of time, separated by a space. The unit of time is used in plural if the integer is greater than 1.

The components are separated by a comma and a space (", "). Except the last component, which is separated by " and ", just like it would be written in English.

A more significant units of time will occur before than a least significant one. Therefore, 1 second and 1 year is not correct, but 1 year and 1 second is.

Different components have different unit of times. So there is not repeated units like in 5 seconds and 1 second.

A component will not appear at all if its value happens to be zero. Hence, 1 minute and 0 seconds is not valid, but it should be just 1 minute.

A unit of time must be used "as much as possible". It means that the function should not return 61 seconds, but 1 minute and 1 second instead. Formally, the duration specified by of a component must not be greater than any valid more significant unit of time.

解答

Solution

function formatDuration(seconds) {
  if (seconds === 0) return "now";

  const times = {
    year: Math.floor(seconds / (365 * 24 * 60 * 60)),
    day: Math.floor((seconds % (365 * 24 * 60 * 60)) / (24 * 60 * 60)),
    hour: Math.floor((seconds % (24 * 60 * 60)) / (60 * 60)),
    minute: Math.floor((seconds % (60 * 60)) / 60),
    second: seconds % 60,
  };

  const resultArr = [];

  for (let i in times) {
    if (times[i] > 0) {
      resultArr.push(`${times[i]} ${i}${times[i] > 1 ? "s" : ""}`);
    }
  }

  return resultArr.length > 1
    ? resultArr.slice(0, -1).join(", ") + " and " + resultArr.slice(-1)
    : resultArr[0];
}

解題思路

就很暴力的遍歷陣列然後換算時間單位秒、分、時、天、年，並儲存到 resultArr 之中，最後把 resultArr 重組成題目要求的字串格式用 ", " 連接多個單位，最後一個單位前加 " and "，並回傳結果。

心得

很單純的題目，但目前只想到暴力解還沒想到可能的優化解。