2020-05-03 09:05:12 +02:00
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/* The selection sort algorithm sorts an array by repeatedly finding the minimum element
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2017-08-14 01:37:18 +05:30
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*(considering ascending order) from unsorted part and putting it at the beginning. The
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*algorithm maintains two subarrays in a given array.
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*1) The subarray which is already sorted.
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*2) Remaining subarray which is unsorted.
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*
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*In every iteration of selection sort, the minimum element (considering ascending order)
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*from the unsorted subarray is picked and moved to the sorted subarray.
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*/
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2020-05-04 11:58:44 +05:30
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2021-10-11 12:29:03 +02:00
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export const selectionSort = (list) => {
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2020-10-05 18:03:52 +00:00
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if (!Array.isArray(list)) {
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throw new TypeError('Given input is not an array')
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}
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const items = [...list] // We don't want to modify the original array
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const length = items.length
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for (let i = 0; i < length - 1; i++) {
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if (typeof items[i] !== 'number') {
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throw new TypeError('One of the items in your array is not a number')
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}
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2020-05-03 09:05:12 +02:00
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// Number of passes
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2020-10-05 18:03:52 +00:00
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let min = i // min holds the current minimum number position for each pass; i holds the Initial min number
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2023-10-03 23:08:19 +02:00
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for (let j = i + 1; j < length; j++) {
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// Note that j = i + 1 as we only need to go through unsorted array
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if (items[j] < items[min]) {
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// Compare the numbers
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2020-05-03 09:05:12 +02:00
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min = j // Change the current min number position if a smaller num is found
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2017-08-14 01:37:18 +05:30
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}
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}
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2020-05-04 11:58:44 +05:30
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if (min !== i) {
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2020-05-03 09:05:12 +02:00
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// After each pass, if the current min num != initial min num, exchange the position.
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// Swap the numbers
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2023-10-03 23:08:19 +02:00
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;[items[i], items[min]] = [items[min], items[i]]
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2017-08-14 01:37:18 +05:30
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}
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}
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2020-10-05 18:03:52 +00:00
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return items
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2017-08-14 01:37:18 +05:30
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}
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