Delete Columns to Make Sorted
<p>You are given an array of <code>n</code> strings <code>strs</code>, all of the same length.</p>

<p>The strings can be arranged such that there is one on each line, making a grid.</p>

<ul>
	<li>For example, <code>strs = [&quot;abc&quot;, &quot;bce&quot;, &quot;cae&quot;]</code> can be arranged as follows:</li>
</ul>

<pre>
abc
bce
cae
</pre>

<p>You want to <strong>delete</strong> the columns that are <strong>not sorted lexicographically</strong>. In the above example (<strong>0-indexed</strong>), columns 0 (<code>&#39;a&#39;</code>, <code>&#39;b&#39;</code>, <code>&#39;c&#39;</code>) and 2 (<code>&#39;c&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;e&#39;</code>) are sorted, while column 1 (<code>&#39;b&#39;</code>, <code>&#39;c&#39;</code>, <code>&#39;a&#39;</code>) is not, so you would delete column 1.</p>

<p>Return <em>the number of columns that you will delete</em>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> strs = [&quot;cba&quot;,&quot;daf&quot;,&quot;ghi&quot;]
<strong>Output:</strong> 1
<strong>Explanation:</strong> 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.
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> strs = [&quot;a&quot;,&quot;b&quot;]
<strong>Output:</strong> 0
<strong>Explanation:</strong> The grid looks as follows:
  a
  b
Column 0 is the only column and is sorted, so you will not delete any columns.
</pre>

<p><strong class="example">Example 3:</strong></p>

<pre>
<strong>Input:</strong> strs = [&quot;zyx&quot;,&quot;wvu&quot;,&quot;tsr&quot;]
<strong>Output:</strong> 3
<strong>Explanation:</strong> The grid looks as follows:
  zyx
  wvu
  tsr
All 3 columns are not sorted, so you will delete all 3.
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>n == strs.length</code></li>
	<li><code>1 &lt;= n &lt;= 100</code></li>
	<li><code>1 &lt;= strs[i].length &lt;= 1000</code></li>
	<li><code>strs[i]</code> consists of lowercase English letters.</li>
</ul>
Array; String
class Solution {
public:
    int minDeletionSize(vector<string>& strs) {
        int m = strs[0].size(), n = strs.size();
        int ans = 0;
        for (int j = 0; j < m; ++j) {
            for (int i = 1; i < n; ++i) {
                if (strs[i][j] < strs[i - 1][j]) {
                    ++ans;
                    break;
                }
            }
        }
        return ans;
    }
};