Find next large number in array

 * Design an efficient algorithm that finds the next index of first occurrence  an element

 * larger than specified key k, return -1 if every element is less than or equal to k 

Well simply using binary search algorithm we can append previous code exist at blog todo own solution 

package Search;
/**
 * Design an efficient algorithm that finds the next index of first occurrence  an element
 * larger than specified key k, return -1 if every element is less than or equal to k 
 *  
 * @copyright GPL
 * @author mohamed fawzy
 *
 */
public class NextLargeNumber {
 
 /**
  * we use binary seach to solve this problem
  * @param a
  * @param k
  * @return int
  */
 public static int search(int a[], int k){
  int low =0;
  int high = a.length-1;
  int middle;
  while(low <= high){
   middle = low + (high-low) /2;
   if(a[middle] == k){
    low = middle+1;
   }else if(a[middle] < k){
    low = middle+1;
   }else{
    return middle;
   }
  }
  return -1;
 }

}

Test case

package Search;

public class NextLargeNumberTest {

 public static void main(String[] args){
  int[] array = {1,2,3,5,6,7,10,20,50};
  int k=20;
  NextLargeNumber nextlargenumber = new NextLargeNumber();
  int result = nextlargenumber.search(array, k);
  System.out.println(result);
 }
}