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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>
55 lines
1.4 KiB
JavaScript
55 lines
1.4 KiB
JavaScript
/**
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* Exponential Search
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*
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* The algorithm consists of two stages. The first stage determines a
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* range in which the search key would reside if it were in the list.
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* In the second stage, a binary search is performed on this range.
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*
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*
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*
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*/
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function binarySearch(arr, value, floor, ceiling) {
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// Middle index
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const mid = Math.floor((floor + ceiling) / 2)
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// If value is at the mid position return this position
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if (arr[mid] === value) {
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return mid
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}
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if (floor > ceiling) return -1
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// If the middle element is great than the value
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// search the left part of the array
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if (arr[mid] > value) {
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return binarySearch(arr, value, floor, mid - 1)
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// If the middle element is lower than the value
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// search the right part of the array
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} else {
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return binarySearch(arr, value, mid + 1, ceiling)
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}
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}
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function exponentialSearch(arr, length, value) {
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// If value is the first element of the array return this position
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if (arr[0] === value) {
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return 0
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}
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// Find range for binary search
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let i = 1
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while (i < length && arr[i] <= value) {
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i = i * 2
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}
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// Call binary search for the range found above
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return binarySearch(arr, value, i / 2, Math.min(i, length))
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}
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export { binarySearch, exponentialSearch }
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// const arr = [2, 3, 4, 10, 40, 65, 78, 100]
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// const value = 78
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// const result = exponentialSearch(arr, arr.length, value)
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