Supermarket

题目描述： 有m个超市，在第i个超市买b千克苹果需要花a元。也就是说，花a/b元可以买1kg苹果。每个超市都无限量供应苹果。你要买n千克苹果，问你最少花多少钱。 输入： 第一行两个正整数n和m(1<=n<=5000,1<=m<=100) 接下来m行，每行两个正整数a和b(1<=a,b<=100) 输出： 一行一个实数，表示你最少花的钱。与标准答案的误差不能超过10^(-6) Translated by AKEE

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.

The first line contains two positive integers $ n $ and $ m $ ( $ 1<=n<=5000 $ , $ 1<=m<=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<=a,b<=100 $ ), denoting that in this supermarket, you are supposed to pay $ a $ yuan for $ b $ kilos of apples.

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 .

3 5
1 2
3 4
1 3

1.66666667

2 1
99 100
98 99

0.98989899

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.