apps_306
Submit solution
Points:
3
Time limit:
30.0s
Memory limit:
250M
Problem type
Allowed languages
Python
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-----
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-----
Print a single integer: the number of possible answers $n$.
-----Examples-----
Input 2 3 5 8
Output 2
Input 4 6 7 13
Output 1
Input 233 233 10007 1
Output 1
-----Note-----
In the first sample, we can see that $n=2$ and $n=8$ are possible answers.
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