47 lines
1.3 KiB
Java
47 lines
1.3 KiB
Java
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//Order Agnostic Binary Search implementation in JAVA
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public class OrderAgnosticBinarySearch {
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static int orderAgnosticBinarySearch(int[] arr, int target) {
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int start = 0;
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int end = arr.length - 1;
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// find whether the array is sorted in ascending or descending
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boolean isAsc = arr[start] < arr[end];
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while(start <= end) {
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// find the middle element
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// int mid = (start + end) / 2;
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// might be possible that (start + end) exceeds the range of int in java
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int mid = start + (end - start) / 2;
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if (arr[mid] == target) {
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return mid;
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}
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if (isAsc) {
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if (target < arr[mid]) {
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end = mid - 1;
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} else {
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start = mid + 1;
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}
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} else {
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if (target > arr[mid]) {
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end = mid - 1;
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} else {
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start = mid + 1;
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}
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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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int[] arr = {1, 5, 10, 20, 30};
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int target = 30;
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int ans = orderAgnosticBinarySearch(arr, target);
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System.out.println(ans);
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}
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}
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//rename to OrderAgnosticBinarySearch to run.
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