Codeforces Round 277 (Div. 2)
E
LIS of Sequence
Codeforces
2200
原题
← D→
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The next "Data Structures and Algorithms" lesson will be about Longest Increasing Subsequence (LIS for short) of a sequence. For better understanding, Nam decided to learn it a few days before the lesson.

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Nam created a sequence $*a*$ consisting of $*n*$ ($1 ≤ *n* ≤ 10^{5}$) elements $*a*_{1}, *a*_{2}, ..., *a*_{*n*}$ ($1 ≤ *a*_{*i*} ≤ 10^{5}$). A subsequence $*a*_{*i*_{1}}, *a*_{*i*_{2}}, ..., *a*_{*i*_{*k*}}$ where $1 ≤ *i*_{1} < *i*_{2} < ... < *i*_{*k*} ≤ *n*$ is called increasing if $*a*_{*i*_{1}} < *a*_{*i*_{2}} < *a*_{*i*_{3}} < ... < *a*_{*i*_{*k*}}$. An increasing subsequence is called longest if it has maximum length among all increasing subsequences.

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Nam realizes that a sequence may have several longest increasing subsequences. Hence, he divides all indexes $*i*$ ($1 ≤ *i* ≤ *n*$), into three groups:

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  1. group of all $*i*$ such that $*a*_{*i*}$ belongs to no longest increasing subsequences.
  2. group of all $*i*$ such that $*a*_{*i*}$ belongs to at least one but not every longest increasing subsequence.
  3. group of all $*i*$ such that $*a*_{*i*}$ belongs to every longest increasing subsequence.
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Since the number of longest increasing subsequences of $*a*$ may be very large, categorizing process is very difficult. Your task is to help him finish this job.

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Input

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The first line contains the single integer $*n*$ ($1 ≤ *n* ≤ 10^{5}$) denoting the number of elements of sequence $*a*$.

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The second line contains $*n*$ space-separated integers $*a*_{1}, *a*_{2}, ..., *a*_{*n*}$ ($1 ≤ *a*_{*i*} ≤ 10^{5}$).

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Output

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Print a string consisting of $*n*$ characters. $*i*$-th character should be '1', '2' or '3' depending on which group among listed above index $*i*$ belongs to.

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Note

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In the second sample, sequence $*a*$ consists of 4 elements: ${*a*_{1}, *a*_{2}, *a*_{3}, *a*_{4}}$ = ${1, 3, 2, 5}$. Sequence $*a*$ has exactly 2 longest increasing subsequences of length 3, they are ${*a*_{1}, *a*_{2}, *a*_{4}}$ = ${1, 3, 5}$ and ${*a*_{1}, *a*_{3}, *a*_{4}}$ = ${1, 2, 5}$.

翻译中…

In the third sample, sequence $*a*$ consists of 4 elements: ${*a*_{1}, *a*_{2}, *a*_{3}, *a*_{4}}$ = ${1, 5, 2, 3}$. Sequence $*a*$ have exactly 1 longest increasing subsequence of length 3, that is ${*a*_{1}, *a*_{3}, *a*_{4}}$ = ${1, 2, 3}$.

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样例

Input #1
1
4
Output #1
3
InputCopy OutputCopy
Input #2
4
1 3 2 5
Output #2
3223
InputCopy OutputCopy
Input #3
4
1 5 2 3
Output #3
3133
InputCopy OutputCopy
题目信息
题号
486E
时间限制
2 s
内存限制
256 MB
标签
数据结构
动态规划
贪心
哈希
数学

题面与样例版权归 Codeforces 及出题人所有;中文翻译由 AI 生成(CI 管线),如有出入请以原文为准。