QUESTION

Consider an array of distinct numbers sorted in increasing order. The array has been rotated (anti-clockwise) k number of times. Given such an array, find the value of k. The number of elements in the array and the elements of the array are the input.

“TESTCASE_1”: “6\n15 18 2 3 6 12\n###—###SEPERATOR—###—\n2”, “TESTCASE_2”: “5\n7 9 11 12 5\n###—###SEPERATOR—###—\n4”, “TESTCASE_3”: “0\n###—###SEPERATOR—###—\n0”, “TESTCASE_4”: “0\n###—###SEPERATOR—###—\n0”, “TESTCASE_5”: “0\n###—###SEPERATOR—###—\n0

ANSWER

// Java program to find number of 
// rotations in a sorted and rotated
// array.
import java.util.*;
import java.lang.*;
import java.io.*;
 
class TestClass
{
    // Returns count of rotations for an 
    // array which is first sorted in 
    // ascending order, then rotated
    static int countRotations(int arr[], int n)
    {
        // We basically find index of minimum
        // element
        int min = arr[0], min_index = -1;
        for (int i = 0; i < n; i++)
        {
            if (min > arr[i])
            {
                min = arr[i];
                min_index = i;
            }
        } 
        return min_index;
    }
 
    // Driver program to test above functions
    public static void main (String[] args) 
    {
      Scanner sc=new Scanner(System.in);
      int n=sc.nextInt();
      int arr[]=new int[n];
      for(int i=0;i<n;i++)
        arr[i]=sc.nextInt();
      
     
        System.out.println(countRotations(arr, n));
    }
}