CF919A.Supermarket

We often go to supermarkets to buy some fruits or vegetables, and on the tag there prints the price for a kilo. But in some supermarkets, when asked how much the items are, the clerk will say that $a$ yuan for $b$ kilos (You don't need to care about what "yuan" is), the same as $a/b$ yuan for a kilo.

Now imagine you'd like to buy $m$ kilos of apples. You've asked $n$ supermarkets and got the prices. Find the minimum cost for those apples.

You can assume that there are enough apples in all supermarkets.

我们经常去超市购买一些水果或蔬菜，商品标签上通常会印有每千克的价格。但在某些超市中，当询问商品价格时，售货员会告诉你“$b$ 千克卖 $a$ 元”（你无需关心“元”是什么货币单位），这等价于每千克 $a/b$ 元。

现在假设你想购买 $m$ 千克苹果。你已向 $n$ 家超市咨询了价格并得到了报价。请计算购买这些苹果的最低总花费。

你可以假设所有超市均有充足的苹果供应。

The first line contains two positive integers $n$ and $m$ ($1 \leq n \leq 5\,000$, $1 \leq m \leq 100$), denoting that there are $n$ supermarkets and you want to buy $m$ kilos of apples.

The following $n$ lines describe the information of the supermarkets. Each line contains two positive integers $a, b$ ($1 \leq a, b \leq 100$), denoting that in this supermarket, you are supposed to pay $a$ yuan for $b$ kilos of apples.

第一行包含两个正整数 $n$ 和 $m$（$1 \leq n \leq 5\,000$，$1 \leq m \leq 100$），表示共有 $n$ 家超市，且你需要购买 $m$ 千克苹果。

接下来的 $n$ 行描述各家超市的信息。每行包含两个正整数 $a$ 和 $b$（$1 \leq a, b \leq 100$），表示在该超市，你需要支付 $a$ 元来购买 $b$ 千克苹果。

The only line, denoting the minimum cost for $m$ kilos of apples. Please make sure that the absolute or relative error between your answer and the correct answer won't exceed $10^{-6}$.

Formally, let your answer be $x$, and the jury's answer be $y$. Your answer is considered correct if $\frac{|x - y|}{\max{(1, |y|)}} \le 10^{-6}$.

唯一的一行，表示购买 $m$ 千克苹果的最小花费。请确保你的答案与正确答案之间的绝对误差或相对误差不超过 $10^{-6}$。

形式化地，设你的答案为 $x$，评测组的答案为 $y$。若满足 $\frac{|x - y|}{\max{(1, |y|)}} \le 10^{-6}$，则你的答案视为正确。

In the first sample, you are supposed to buy $5$ kilos of apples in supermarket $3$. The cost is $5/3$ yuan.

In the second sample, you are supposed to buy $1$ kilo of apples in supermarket $2$. The cost is $98/99$ yuan.

在第一个样例中，您需要在超市 3 购买 $5$ 千克苹果，花费为 $5/3$ 元。

在第二个样例中，您需要在超市 2 购买 $1$ 千克苹果，花费为 $98/99$ 元。