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Time Limit: 1.5 s Memory Limit: 256 MB Total points: 100

#10135. 孑孓王可

統計

$\text{***}$,$\text{**}$想你了。

题目描述

有一个无限长的数列 $A$,初始时 $A$ 中元素全为 $0$。

给定 $n$ 个区间 $[l_i,r_i]$,对于 $i=1,2,\ldots,n$,你需要执行以下的一种操作恰好一次:

  1. $\forall j\in [l_i,r_i]$,令 $A_j\gets A_j+1$。
  2. $\forall j \in \mathbb Z \land j\not\in [l_i,r_i]$,令 $A_j\gets A_j+1$。

构造一组方案,使得操作完后数列中最大值最小。

输入格式

第一行,一个正整数 $n$。

接下来 $n$ 行,第 $i$ 行两个正整数 $l_i,r_i$。

输出格式

第一行,一个正整数,表示最小化的最大值。

第二行输出一个长度为 $n$ 的 $\texttt{01}$ 串 $s$:

  • $s_i=\texttt{0}$,表示对于 $i$ 选择操作 $\text{2}$
  • $s_i=\texttt{1}$,表示对于 $i$ 选择操作 $\text{1}$

样例一

input

5
10 10
6 6
1 7
2 5
2 7

output

2
11110

explanation

另一种合法的输出为

2
11011

限制与约定

对于 $100\%$ 的数据,保证:

  • $1\le n\le 2\times 10^5$;
  • $1\le l_i\le r_i\le 2n$。
子任务编号 $n\le$ 得分
$1$ $20$ $7$
$2$ $150$ $24$
$3$ $10^3$ $21$
$4$ $5\times 10^4$ $34$
$5$ $2\times 10^5$ $14$

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