Give me idea for the following problem.

The positive divisor function is defined as a function that counts the number of positive divisors of an integer N, including 1 and N. If we define the positive divisor function as D(N), then, for example: D(24) = 8 (Because 24 has 8 divisors and they are 1, 2, 3, 4, 6, 8, 12, 24) Calculating D(N) is a classical problem and there are many efficient algorithms for that. But what if you are asked to find something different? Given a range and an integer K, can you find out for how many N in the given range, D(N) equals K?

Input In the very first line, you’ll have an integer called T. This is the number of test cases that shall follow. Every test case contains three integers, L, R, and K. L and R represent the range and are inclusive.

Constraints ● 1 ≤ T < 31 ● 1 ≤ L ≤ R < 2 31 ● 1 ≤ K < 2 31

Output For every test case, you must print the case number, followed by the count of numbers with exactly K divisors in the range.