Problem E

Statement
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Description:
Given an integer $$$x$$$. Your task is to find out how many positive integers $$$n$$$ ($$$1 \leq n \leq x$$$) satisfy $$$$$$n \cdot a^n \equiv b \quad (\textrm{mod}\;p),$$$$$$ where $$$a, b, p$$$ are all known constants.

Input Format:
The only line contains four integers $$$a,b,p,x$$$ ($$$2 \leq p \leq 10^6+3$$$, $$$1 \leq a,b < p$$$, $$$1 \leq x \leq 10^{12}$$$). It is guaranteed that $$$p$$$ is a prime.

Output Format:
Print a single integer: the number of possible answers $$$n$$$.

Note:
In the first sample, we can see that $$$n=2$$$ and $$$n=8$$$ are possible answers.