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Discussion on: Daily Challenge #94 - Last Digit

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Balaji K

Javascript

const lastDigit = (digits) => {
  if(!digits.length) return '1';
  let power = digits.reduceRight((a, b) => Math.pow(b, a));

  power = (!isFinite(power) || isNaN(power)) ? '0' : String(power);

  return power.slice(power.length - 1, power.length);
}

lastDigit([9, 9]); Output: '9'
lastDigit([9, 9, 9]); Output: '0'
lastDigit([]); Output: '1'

Not sure how to get the last digit from more than 369 million of digits, so handled it with 0 and empty list as 1.