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Time Limit: 1 s Memory Limit: 256 MB Total points: 100

#6423. 烟花

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Kotori 正在为即将到来的花火大会练习制作烟花。制作一枚烟花需要 $n$ 分钟,由于她制作烟花的技术并不熟练,每枚烟花只有 $p \times 10^{-4}$ 的概率是完美的。

在制作完一枚烟花后,她可以选择立即开始制作下一枚烟花,或者花费 $m$ 分钟点燃之前所有已完成的烟花。如果点燃的烟花中至少有一枚是完美的,她就会感到满意并去休息。否则,她将继续练习。如果她采取最优策略,你能告诉她去休息前所需的最小期望练习时间吗?

注意,无论剩余多少枚烟花,点燃它们总是需要 $m$ 分钟。

输入格式

输入包含多组测试数据。第一行包含一个整数 $T$ ($1 \le T \le 10^4$),表示测试数据的组数。对于每组测试数据:

第一行包含三个整数 $n, m$ 和 $p$ ($1 \le n, m \le 10^9, 1 \le p \le 10^4$)。

输出格式

对于每组测试数据,输出一行,包含一个数字,表示最小期望练习时间。

如果你的答案与标准答案的绝对误差或相对误差不超过 $10^{-4}$,则视为正确。

样例

样例输入 1

3
1 1 5000
1 1 1
1 2 10000

样例输出 1

4.0000000000
10141.5852891136
3.0000000000

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