JavaAlgorithms/Searches/LinearSearch.java
2018-11-13 09:15:47 -08:00

64 lines
1.7 KiB
Java

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