1
var numberOfRounds = function (loginTime, logoutTime) {
2
  const start = toMins(loginTime);
3
  const end = toMins(logoutTime);
4

5
  let roundStart = Math.ceil(start / 15);
6
  let roundEnd = Math.floor(end / 15);
7

8
  if (start < end) {
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    return Math.max(0, roundEnd - roundStart);
10
  } else {
11
    roundEnd += 96;
12
    return roundEnd - roundStart;
13
  }
14

15
  function toMins(timeStr) {
16
    const [hh, mm] = timeStr.split(":");
17

18
    let totMins = 0;
19

20
    totMins += parseInt(hh) * 60;
21
    totMins += parseInt(mm);
22

23
    return totMins;
24
  }
25
};