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31 lines
686 B
JavaScript
31 lines
686 B
JavaScript
/**
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* @param {number} number
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* @return {boolean}
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*/
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export default function isPowerOfTwo(number) {
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// Don't work with negative numbers.
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if (number < 0) {
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throw new Error('Please provide positive number');
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}
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// 0 and 1 are not powers of two.
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if (number <= 1) {
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return false;
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}
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// Let's find out if we can divide the number by two
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// many times without remainder.
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let dividedNumber = number;
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while (dividedNumber !== 1) {
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if (dividedNumber % 2 !== 0) {
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// For every case when remainder isn't zero we can say that this number
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// couldn't be a result of power of two.
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return false;
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}
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dividedNumber /= 2;
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}
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return true;
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}
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