Xiao $\Omega$ learned the concept of "powers" in elementary school mathematics: $\forall a, b \in \mathbb{N}^+$, $a^b$ is defined as the product of $b$ copies of $a$.
She is curious about how many positive integers can be represented in the form $a^b$ mentioned above. Since all positive integers $m \in \mathbb{N}^+$ can always be represented as $m^1$, she requires that in the representation above, $b \geq k$, where $k$ is a positive integer she has chosen in advance.
Therefore, she wants to know how many positive integers $x$ in the range $1$ to $n$ can be represented in the form $x = a^b$, where $a$ and $b$ are both positive integers and $b \geq k$.
Input
The input contains two positive integers $n$ and $k$, as described above.
Output
Output a single non-negative integer representing the corresponding answer.
Examples
Input 1
99 1
Output 1
99
Note 1
Since all positive integers $x \in [1, 99]$ can be represented as $x = x^1$, the answer is $99$.
Input 2
99 3
Output 2
7
Note 2
The following are all 7 positive integers that satisfy the condition and one valid representation for each:
$1 = 1^3, 8 = 2^3, 16 = 2^4, 27 = 3^3, 32 = 2^5, 64 = 4^3, 81 = 3^4$
Note that some positive integers may have multiple valid representations, for example, $64$ can also be represented as $64 = 2^6$. However, according to the problem, different valid representations of the same number are only counted once.
Input 3
99 2
Output 3
12
Note 3
The following are all 12 positive integers that satisfy the condition and one valid representation for each:
$1 = 1^2, 4 = 2^2, 8 = 2^3, 9 = 3^2, 16 = 4^2, 25 = 5^2$ $27 = 3^3, 32 = 2^5, 36 = 6^2, 49 = 7^2, 64 = 8^2, 81 = 9^2$
Input 4
power/power4.in
Output 4
power/power4.ans
Input 5
power/power5.in
Output 5
power/power5.ans
Input 6
power/power6.in
Output 6
power/power6.ans
Constraints
For all data, it is guaranteed that $1 \leq n \leq 10^{18}$ and $1 \leq k \leq 100$.
| Test Case ID | $n \leq$ | $k$ |
|---|---|---|
| 1 | $10^2$ | $= 1$ |
| 2 | $\geq 2$ | |
| 3 | $10^4$ | $\geq 3$ |
| 4 | $\geq 2$ | |
| 5 | $10^6$ | $\geq 3$ |
| 6 | $\geq 2$ | |
| 7 | $10^8$ | $\geq 3$ |
| 8 | $\geq 2$ | |
| 9 | $10^{10}$ | $\geq 3$ |
| 10 | $\geq 2$ | |
| 11 | $10^{12}$ | $\geq 3$ |
| 12 | $\geq 2$ | |
| 13 | $10^{14}$ | $\geq 3$ |
| 14 | $\geq 2$ | |
| 15 | $10^{16}$ | $\geq 3$ |
| 16 | $\geq 2$ | |
| 17 | $10^{18}$ | $\geq 3$ |
| 18 | ||
| 19 | $\geq 2$ | |
| 20 |