CF1041B.Buying a TV Set

Monocarp has decided to buy a new TV set and hang it on the wall in his flat. The wall has enough free space so Monocarp can buy a TV set with screen width not greater than $a$ and screen height not greater than $b$. Monocarp is also used to TV sets with a certain aspect ratio: formally, if the width of the screen is $w$, and the height of the screen is $h$, then the following condition should be met: $\frac{w}{h} = \frac{x}{y}$.

There are many different TV sets in the shop. Monocarp is sure that for any pair of positive integers $w$ and $h$ there is a TV set with screen width $w$ and height $h$ in the shop.

Monocarp isn't ready to choose the exact TV set he is going to buy. Firstly he wants to determine the optimal screen resolution. He has decided to try all possible variants of screen size. But he must count the number of pairs of positive integers $w$ and $h$, beforehand, such that $(w \le a)$, $(h \le b)$ and $(\frac{w}{h} = \frac{x}{y})$.

In other words, Monocarp wants to determine the number of TV sets having aspect ratio $\frac{x}{y}$, screen width not exceeding $a$, and screen height not exceeding $b$. Two TV sets are considered different if they have different screen width or different screen height.

Monocarp 决定购买一台新电视，并将其悬挂在自己公寓的墙上。墙面有足够的空余空间，因此 Monocarp 可以购买屏幕宽度不超过 $a$、高度不超过 $b$ 的电视。此外，Monocarp 习惯使用具有特定长宽比的电视：形式化地说，若屏幕宽度为 $w$、高度为 $h$，则需满足条件 $\frac{w}{h} = \frac{x}{y}$。

商店中出售种类繁多的电视。Monocarp 确信：对任意一对正整数 $w$ 和 $h$，商店中均存在一台屏幕宽度为 $w$、高度为 $h$ 的电视。

Monocarp 尚未决定具体购买哪一台电视。他首先希望确定最优的屏幕分辨率。他计划尝试所有可能的屏幕尺寸组合，但必须预先计算出满足以下条件的正整数对 $(w, h)$ 的数量：$(w \le a)$、$(h \le b)$ 且 $(\frac{w}{h} = \frac{x}{y})$。

换言之，Monocarp 想要求出满足长宽比为 $\frac{x}{y}$、屏幕宽度不超过 $a$、屏幕高度不超过 $b$ 的电视台数。若两台电视的屏幕宽度不同或屏幕高度不同，则视为不同的电视。

The first line contains four integers $a$, $b$, $x$, $y$ ($1 \le a, b, x, y \le 10^{18}$) — the constraints on the screen width and height, and on the aspect ratio.

第一行包含四个整数 $a$、$b$、$x$、$y$（$1 \le a, b, x, y \le 10^{18}$）——分别表示屏幕宽高及长宽比的约束条件。

Print one integer — the number of different variants to choose TV screen width and screen height so that they meet the aforementioned constraints.

输出一个整数——满足上述约束条件的不同电视屏幕宽度和高度组合的数量。

In the first example, there are $3$ possible variants: $(5, 3)$, $(10, 6)$, $(15, 9)$.

In the second example, there is no TV set meeting the constraints.

In the third example, there is only one variant: $(3, 2)$.

在第一个例子中，有 $3$ 种可能的方案：$(5, 3)$、$(10, 6)$、$(15, 9)$。

在第二个例子中，不存在满足约束条件的电视机。

在第三个例子中，仅有一种方案：$(3, 2)$。