Here's a few variations that will work.
const oneLiner = (hour = "00", min = "00", sec = "00") => `${(hour % 12) || 12}:${("0" + min).slice(-2)}:${sec} ${(hour < 12) ? 'am' : 'pm'}`_x000D_
console.log('oneliner', oneLiner(..."13:05:12".split(":")))_x000D_
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const oneLinerWithObjectInput = ({hour = "00", min = "00", sec = "00"} = {}) => `${(hour % 12) || 12}:${("0" + min).slice(-2)}:${sec} ${(hour < 12) ? 'am' : 'pm'}`_x000D_
console.log('onelinerWithObjectInput', oneLinerWithObjectInput({_x000D_
hour: "13:05:12".split(":")[0],_x000D_
min: "13:05:12".split(":")[1],_x000D_
sec: "13:05:12".split(":")[2]_x000D_
}))_x000D_
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const multiLineWithObjectInput = ({hour = "00", min = "00", sec = "00"} = {}) => {_x000D_
const newHour = (hour % 12) || 12_x000D_
, newMin = ("0" + min).slice(-2)_x000D_
, ampm = (hour < 12) ? 'am' : 'pm'_x000D_
return `${newHour}:${newMin}:${sec} ${ampm}`_x000D_
}_x000D_
console.log('multiLineWithObjectInput', multiLineWithObjectInput({_x000D_
hour: "13:05:12".split(":")[0],_x000D_
min: "13:05:12".split(":")[1],_x000D_
sec: "13:05:12".split(":")[2]_x000D_
}))
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