fix: replace .chinese.md extension with .md

curriculum/challenges/chinese/10-coding-interview-prep/project-euler/problem-250-250250.md

@@ -0,0 +1,56 @@
+---
+id: 5900f4661000cf542c50ff78
+challengeType: 5
+title: 'Problem 250: 250250'
+videoUrl: ''
+localeTitle: 问题250：250250
+---
+
+## Description
+<section id="description">找到{11,22,33，...，250250250250}的非空子集的数量，其元素的总和可被250整除。输入最右边的16位作为答案。 </section>
+
+## Instructions
+<section id="instructions">
+</section>
+
+## Tests
+<section id='tests'>
+
+```yml
+tests:
+  - text: <code>euler250()</code>应该返回1425480602091519。
+    testString: assert.strictEqual(euler250(), 1425480602091519);
+
+```
+
+</section>
+
+## Challenge Seed
+<section id='challengeSeed'>
+
+<div id='js-seed'>
+
+```js
+function euler250() {
+  // Good luck!
+  return true;
+}
+
+euler250();
+
+```
+
+</div>
+
+
+
+</section>
+
+## Solution
+<section id='solution'>
+
+```js
+// solution required
+```
+
+/section>