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ACM-ICPC亚洲区预选赛(北京赛区)游戏对抗邀请赛​正在报名中

Language:
Discrete Logging
 Time Limit: 5000MS Memory Limit: 65536K Total Submissions: 5331 Accepted: 2413

Description

Given a prime P, 2 <= P < 231, an integer B, 2 <= B < P, and an integer N, 1 <= N < P, compute the discrete logarithm of N, base B, modulo P. That is, find an integer L such that
`    BL == N (mod P)`

Input

Read several lines of input, each containing P,B,N separated by a space.

Output

For each line print the logarithm on a separate line. If there are several, print the smallest; if there is none, print "no solution".

Sample Input

```5 2 1
5 2 2
5 2 3
5 2 4
5 3 1
5 3 2
5 3 3
5 3 4
5 4 1
5 4 2
5 4 3
5 4 4
12345701 2 1111111
1111111121 65537 1111111111
```

Sample Output

```0
1
3
2
0
3
1
2
0
no solution
no solution
1
9584351
462803587
```

Hint

The solution to this problem requires a well known result in number theory that is probably expected of you for Putnam but not ACM competitions. It is Fermat's theorem that states
`   B(P-1) == 1 (mod P)`

for any prime P and some other (fairly rare) numbers known as base-B pseudoprimes. A rarer subset of the base-B pseudoprimes, known as Carmichael numbers, are pseudoprimes for every base between 2 and P-1. A corollary to Fermat's theorem is that for any m
`   B(-m) == B(P-1-m) (mod P) .`

Source

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