46. Binary Search Implementation

• 
  public static int binarySearch(int[] list, int listLength,
          int searchItem) {
      int first = 0;
      int last = listLength - 1;
      int mid = 0;
      boolean found = false;
  
      while (first <= last && !found) {
          mid = (first + last) / 2;
          if (list[mid] == searchItem) {
              found = true;
          } else if (list[mid] > searchItem) {
              last = mid - 1;
          } else {
              first = mid + 1;
          }
      }
      if (found) {
          return mid;
      } else {
          return -1;
      }
  } //end binarySearch