int[] numbersArray = {1,3,4,6,7,8,10,13,14,18,19,21,24,37,40,45,71};
public boolean binarySearchAlgorithm(int targetNumber, int[] numbers)
{
    int lowerLimit = 0;
    int upperLimit = numbers.length - 1;

    while (upperLimit >= lowerLimit)
    {
        int middleNumber = (lowerLimit + upperLimit)/2;

        if (numbers[middleNumber] == targetNumber)
        {
            return true;
        }
        if (numbers[middleNumber] < targetNumber)
        {
            lowerLimit = middleNumber + 1;
        }
        if (numbers[middleNumber] > targetNumber)
        {
            upperLimit = middleNumber - 1;
        }
    }
    return false;
}
System.out.println(binarySearchAlgorithm(7, numbersArray)); //prints "true"