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86d333ee94
* chore: Switch to Node 20 + Vitest * chore: migrate to vitest mock functions * chore: code style (switch to prettier) * test: re-enable long-running test Seems the switch to Node 20 and Vitest has vastly improved the code's and / or the test's runtime! see #1193 * chore: code style * chore: fix failing tests * Updated Documentation in README.md * Update contribution guidelines to state usage of Prettier * fix: set prettier printWidth back to 80 * chore: apply updated code style automatically * fix: set prettier line endings to lf again * chore: apply updated code style automatically --------- Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com> Co-authored-by: Lars Müller <34514239+appgurueu@users.noreply.github.com>
35 lines
706 B
JavaScript
35 lines
706 B
JavaScript
/*
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Program to get the Nth Lucas Number
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Article on Lucas Number: https://en.wikipedia.org/wiki/Lucas_number
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Examples:
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> loopLucas(1)
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1
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> loopLucas(20)
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15127
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> loopLucas(100)
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792070839848372100000
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*/
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/**
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* @param {Number} index The position of the number you want to get from the Lucas Series
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*/
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function lucas(index) {
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// index can't be negative
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if (index < 0) throw new TypeError('Index cannot be Negative')
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// index can't be a decimal
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if (Math.floor(index) !== index)
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throw new TypeError('Index cannot be a Decimal')
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let a = 2
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let b = 1
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for (let i = 0; i < index; i++) {
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const temp = a + b
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a = b
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b = temp
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}
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return a
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}
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export { lucas }
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