def calculateSum(n1, n2):
    flag = 0
    primes = []
    a = n1
    b = n2
    for i in range(a, b):
        if (i == 1):
            continue

        flag = 1

        for j in range(2, i // 2 + 1):
            if (i % j == 0):
                flag = 0
                break

        if (flag == 1):
            primes.append(i)

    max_val = max(primes)
    if len(primes) == 1:
        return primes[0]
    return sum([abs(max_val - a) for a in primes])