Usage: Perform a binary search. Enter a key as a number. Click the Next button to perform one comparison. Click the Reset button to start over with a new random list of the specified size (min 3 and max 20). The Custom Input button enables you to enter a custom list.

low: 0

↓

mid: 1

↓

high: 1

↓

Set list size: Key: Next Reset Custom Input

A list is filled with random numbers.

  1    int binarySearch(const int list[], int key, int arraySize)
  2    {
  2      int low = 0;
  3      int high = arraySize - 1;
  4  
  5      while (high >= low)
  6      {
  6        int mid = (low + high) / 2;
  7        if (key < list[mid])
  8          high = mid - 1;
  9        else if (key == list[mid])
 11          return mid;
 12        else
 13          low = mid + 1;
 14      }
 15  
 16      return -low - 1; // Now high < low
 17    }