class BinarySearchExample{
public static void binarySearch(int arr[], int first, int last, int key){
int mid = (first + last)/2;
while( first <= last ){
if ( arr[mid] < key ){
first = mid + 1;
}else if ( arr[mid] == key ){
System.out.println("Element is found at index: " + mid);
break;
}else{
last = mid - 1;
}
mid = (first + last)/2;
}
if ( first > last ){
System.out.println("Element is not found!");
}
}
public static void main(String args[]){
int arr[] = {10,20,30,40,50};
int key = 30;
int last=arr.length-1;
binarySearch(arr,0,last,key);
}
}