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# 0944. Delete Columns to Make Sorted

<https://leetcode.com/problems/delete-columns-to-make-sorted>

## Description

You are given an array of `n` strings `strs`, all of the same length.

The strings can be arranged such that there is one on each line, making a grid. For example, `strs = ["abc", "bce", "cae"]` can be arranged as:

```
abc
bce
cae
```

You want to **delete** the columns that are **not sorted lexicographically**. In the above example (0-indexed), columns 0 (`'a'`, `'b'`, `'c'`) and 2 (`'c'`, `'e'`, `'e'`) are sorted while column 1 (`'b'`, `'c'`, `'a'`) is not, so you would delete column 1.

Return *the number of columns that you will delete*.

**Example 1:**

```
**Input:** strs = ["cba","daf","ghi"]
**Output:** 1
**Explanation:** The grid looks as follows:
  cba
  daf
  ghi
Columns 0 and 2 are sorted, but column 1 is not, so you only need to delete 1 column.
```

**Example 2:**

```
**Input:** strs = ["a","b"]
**Output:** 0
**Explanation:** The grid looks as follows:
  a
  b
Column 0 is the only column and is sorted, so you will not delete any columns.
```

**Example 3:**

```
**Input:** strs = ["zyx","wvu","tsr"]
**Output:** 3
**Explanation:** The grid looks as follows:
  zyx
  wvu
  tsr
All 3 columns are not sorted, so you will delete all 3.
```

**Constraints:**

* `n == strs.length`
* `1 <= n <= 100`
* `1 <= strs[i].length <= 1000`
* `strs[i]` consists of lowercase English letters.

## ac

```java
```