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leetcode/problem/drop-missing-data.html

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+<pre>
+DataFrame students
++-------------+--------+
+| Column Name | Type   |
++-------------+--------+
+| student_id  | int    |
+| name        | object |
+| age         | int    |
++-------------+--------+
+</pre>
+
+<p>There are some rows having missing values in the <code>name</code> column.</p>
+
+<p>Write a solution to remove the rows with missing values.</p>
+
+<p>The result format is in the following example.</p>
+
+<p>&nbsp;</p>
+<p><strong class="example">Example 1:</strong></p>
+
+<pre>
+<strong>Input:
+</strong>+------------+-------+-----+
+| student_id | name  | age |
++------------+-------+-----+
+| 32         | Piper | 5   |
+| 217        | Grace | 19  |
+| 779        | None  | 20  |
+| 849        | None  | 14  |
++------------+-------+-----+
+<strong>Output:
+</strong>+------------+-------+-----+
+| student_id | name  | age |
++------------+-------+-----+
+| 32         | Piper | 5   |
+| 217        | Grace | 19  |
++------------+-------+-----+
+<strong>Explanation:</strong> 
+Students with ids 779 and 849 have empty values in the name column, so they will be removed.</pre>