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# 0484. Find Permutation

<https://leetcode.com/problems/find-permutation>

## Description

A permutation `perm` of `n` integers of all the integers in the range `[1, n]` can be represented as a string `s` of length `n - 1` where:

* `s[i] == 'I'` if `perm[i] < perm[i + 1]`, and
* `s[i] == 'D'` if `perm[i] > perm[i + 1]`.

Given a string `s`, reconstruct the lexicographically smallest permutation `perm` and return it.

**Example 1:**

```
**Input:** s = "I"
**Output:** [1,2]
**Explanation:** [1,2] is the only legal permutation that can represented by s, where the number 1 and 2 construct an increasing relationship.
```

**Example 2:**

```
**Input:** s = "DI"
**Output:** [2,1,3]
**Explanation:** Both [2,1,3] and [3,1,2] can be represented as "DI", but since we want to find the smallest lexicographical permutation, you should return [2,1,3]
```

**Constraints:**

* `1 <= s.length <= 105`
* `s[i]` is either `'I'` or `'D'`.

## ac

```java
```