2021-10-26 15:00:07 +05:30
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/*
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A program to calculate the Aliquot Sum of a number.
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The aliquot sum of a number n, is the sum of all the proper divisors of n apart from n itself
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For example, for the number 6
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The divisors are 1, 2, 3 (we don't consider 6), so its aliquot sum is 1 + 2 + 3 = 6
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1 is the only number whose aliquot sum is 0 (since its only divisor is 1 and aliquot sum of a number couldn't have itself)
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For all prime numbers, the aliquot sum is 1, since their only divisor apart from themselves is 1
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Article on Aliquot Sum: https://en.wikipedia.org/wiki/Aliquot_sum
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*/
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/**
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* @param {Number} input The number whose aliquot sum you want to calculate
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*/
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2023-10-03 23:08:19 +02:00
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function aliquotSum(input) {
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2021-10-26 15:00:07 +05:30
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// input can't be negative
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if (input < 0) throw new TypeError('Input cannot be Negative')
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// input can't be a decimal
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2023-10-03 23:08:19 +02:00
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if (Math.floor(input) !== input)
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throw new TypeError('Input cannot be a Decimal')
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2021-10-26 15:00:07 +05:30
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// Dealing with 1, which isn't a prime
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if (input === 1) return 0
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let sum = 0
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2023-10-03 23:08:19 +02:00
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for (let i = 1; i <= input / 2; i++) {
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2021-10-26 15:00:07 +05:30
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if (input % i === 0) sum += i
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}
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return sum
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}
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export { aliquotSum }
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