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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>
48 lines
1.6 KiB
JavaScript
48 lines
1.6 KiB
JavaScript
/**
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* Sliding Window:
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* This pattern involve creating a window which can either be
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* an array or numbers from one position to another.
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*
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* Depending on a certain condition, the window either increases
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* or closes (and a new window is created).
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*
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* Very useful for keeping track of a subset of data in an
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* array/string etc.
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*
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* Time Complexity: Best - O(n);
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*
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* Examples:
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* maxSubarraySum([1,2,5,2,8,1,5],2) // returns 10
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* maxSubarraySum([1,2,5,2,8,1,5],15) // returns null
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* maxSubarraySum([5,2,6,9],3) // returns 17
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* @param {[Int]} arr - An array of integers on which we will perform the test.
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* @param {Int} num - An integer that displays the size of the window you want to check.
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* @returns {Int / Null} - Returns a total of N consecutive numbers or null
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*/
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function slidingWindow(arr, num) {
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// Edge Case:
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// If the length of the array shorter than the window size (num) return null.
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if (arr.length < num) return null
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// The highest amount of consecutive numbers
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let maxSum = 0
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// Temp amount of consecutive numbers - For comparative purposes
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let tempSum = 0
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// loop over the array {num} times and save their total amount in {maxSum}
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for (let i = 0; i < num; i++) {
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maxSum += arr[i]
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}
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// initialize {tempSum} to {maxSum}.
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tempSum = maxSum
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// loop over the array n times
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for (let i = num; i < arr.length; i++) {
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// Add the next num in the array and remove the first one
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tempSum = tempSum - arr[i - num] + arr[i]
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// save the largest number between {maxNum} and {tempNum} in maxSum.
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maxSum = Math.max(maxSum, tempSum)
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}
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return maxSum
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}
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export { slidingWindow }
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