48 lines
1.3 KiB
Java
48 lines
1.3 KiB
Java
/*
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Order Agnostic Binary Search is a method of finding the sorted array in either ascending or descending order.
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*/
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public class OrderAgnosticBS {
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public static void main(String[] args) {
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int[] arr={1,2,3,4,5,6,7,8,9};
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int target=7;
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int ans=orderAgnosticBS(arr,target);
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System.out.println(ans);
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}
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static int orderAgnosticBS(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 array is sorted in ascending or descending order
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boolean isAsc;// boolean isAsc = arr[start]<arr[send];
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if(arr[start]<arr[end]){
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isAsc=true;
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}
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else{
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isAsc=false;
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}
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while(start<=end){
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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(arr[mid]>target) {
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end=mid-1;
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}
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else if(arr[mid]<target){
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start=mid+1;
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}
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}
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else{
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if(arr[mid]<target) {
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end=mid-1;
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}
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else if(arr[mid]>target){
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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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}
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