64 lines
1.7 KiB
Java
64 lines
1.7 KiB
Java
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package search;
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import java.util.Random;
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import java.util.stream.Stream;
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/**
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* Linear search is the easiest search algorithm
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* It works with sorted and unsorted arrays (an binary search works only with sorted array)
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* This algorithm just compares all elements of an array to find a value
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*
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* Worst-case performance O(n)
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* Best-case performance O(1)
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* Average performance O(n)
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* Worst-case space complexity
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*
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*
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* @author Varun Upadhyay (https://github.com/varunu28)
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* @author Podshivalov Nikita (https://github.com/nikitap492)
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*
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*
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* @see BinarySearch
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* @see SearchAlgorithm
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*/
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public class LinearSearch implements SearchAlgorithm {
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/**
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* Generic Linear search method
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*
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* @param array List to be searched
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* @param value Key being searched for
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* @return Location of the key
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*/
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@Override
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public <T extends Comparable<T>> int find(T[] array, T value) {
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for (int i = 0; i < array.length ; i++) {
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if (array[i].compareTo(value) == 0) {
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return i;
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}
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}
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return -1;
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}
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public static void main(String[] args) {
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//just generate data
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Random r = new Random();
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int size = 200;
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int maxElement = 100;
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Integer[] integers = Stream.generate(() -> r.nextInt(maxElement)).limit(size).toArray(Integer[]::new);
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//the element that should be found
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Integer shouldBeFound = integers[r.nextInt(size - 1)];
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LinearSearch search = new LinearSearch();
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int atIndex = search.find(integers, shouldBeFound);
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System.out.println(String.format("Should be found: %d. Found %d at index %d. An array length %d"
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, shouldBeFound, integers[atIndex], atIndex, size));
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}
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}
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