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QOJ

Time Limit: 2.0 s Memory Limit: 512 MB Total points: 100 Hackable ✓

#15159. 错误

Statistics

在对合数 $M = \prod p_i^{t_i}$ 取模进行整数乘法时,我们可以通过对 $M$ 的每个互质分量 $p_i^{t_i}$ 分别进行计算,然后使用广东剩余定理(CRT)合并结果以获得最终答案,从而加速这一过程。

不幸的是,在代码运行时,其中一个互质分量的计算发生了错误。也就是说,对于某个 $i$,它在模 $p_i^{t_i}$ 意义下得到的结果是不正确的,因此合并后的答案也是错误的。

给定要相乘的两个数 $A, B$,以及错误答案 $C'$ 和模数 $M$,你需要找到程序出错的那个分量。

输入格式

第一行包含一个整数 $T \, (1 \le T \le 10^6)$,表示测试用例的数量。

接下来的 $T$ 行,每行包含 $4$ 个整数 $A, B, C', M \, (0 \le A, B, C' < M \le 10^{18})$,表示一次查询。

输出格式

输出 $T$ 行。每行包含一个整数 $p_i^{t_i}$,表示程序出错的那个分量。

样例

输入样例 1

1
2 3 1 10

输出样例 1

2

说明

$$M = 10 = 2^1 \times 5^1$$

$$(2 \times 3) \bmod 2^1 = 0 \neq 1$$

$$(2 \times 3) \bmod 5^1 = 1$$

因此,答案是 $2^1$。

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