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#10900. 奇怪的函数

الإحصائيات

给定 $n$ 个函数 $f_1(x), f_2(x), \dots, f_n(x)$,其中 $$f_i(x) = \begin{cases} |\arctan(k_i \sec(x - a_i))| & (x \neq a_i + (k + \frac{1}{2})\pi \text{ 其中 } k = 0, \pm 1, \pm 2, \dots) \\ \frac{\pi}{2} & (x = a_i + (k + \frac{1}{2})\pi \text{ 其中 } k = 0, \pm 1, \pm 2, \dots) \end{cases}$$ 对于每个函数 $f_i(x)$,判断是否存在一个 $x_i$ 使得对于所有的 $j \in {1, 2, \dots, i-1, i+1, \dots, n}$,都有 $f_i(x_i) < f_j(x_i)$。 注意: * "arctan" 是 "tan" 的反函数。 * $\sec(x) = \frac{1}{\cos(x)}$。

输入格式

第一行包含一个整数 $n$ ($1 \le n \le 10^5$),表示给定函数的数量。 接下来 $n$ 行,每行包含两个整数 $k_i, a_i$ ($1 \le k_i \le 10^5, |a_i| \le 10^5$),表示给定的函数。 保证对于任意 $1 \le i < j \le n$,都有 $k_i \neq k_j$ 或 $a_i \neq a_j$。

输出格式

输出一行,包含一个长度为 $n$ 的 01 字符串 $S$,其中如果存在这样的 $x_i$,则 $S_i = 1$,否则 $S_i = 0$。

样例

输入 1

3
1 1
3 2
2 3

输出 1

101

说明

下图展示了样例的情况。

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