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curriculum/challenges/english/10-coding-interview-prep/project-euler/problem-262-mountain-range.md

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+---
+id: 5900f4731000cf542c50ff85
+challengeType: 5
+title: 'Problem 262: Mountain Range'
+forumTopicId: 301911
+---
+
+## Description
+<section id='description'>
+The following equation represents the continuous topography of a mountainous region, giving the elevation h at any point (x,y):
+
+
+
+
+A mosquito intends to fly from A(200,200) to B(1400,1400), without leaving the area given by 0 ≤ x, y ≤ 1600.
+
+Because of the intervening mountains, it first rises straight up to a point A', having elevation f. Then, while remaining at the same elevation f, it flies around any obstacles until it arrives at a point B' directly above B.
+
+First, determine fmin which is the minimum constant elevation allowing such a trip from A to B, while remaining in the specified area.
+Then, find the length of the shortest path between A' and B', while flying at that constant elevation fmin.
+
+Give that length as your answer, rounded to three decimal places.
+
+Note: For convenience, the elevation function shown above is repeated below, in a form suitable for most programming languages:
+h=( 5000-0.005*(x*x+y*y+x*y)+12.5*(x+y) ) * exp( -abs(0.000001*(x*x+y*y)-0.0015*(x+y)+0.7) )
+</section>
+
+## Instructions
+<section id='instructions'>
+
+</section>
+
+## Tests
+<section id='tests'>
+
+```yml
+tests:
+  - text: <code>euler262()</code> should return 2531.205.
+    testString: assert.strictEqual(euler262(), 2531.205);
+
+```
+
+</section>
+
+## Challenge Seed
+<section id='challengeSeed'>
+
+<div id='js-seed'>
+
+```js
+function euler262() {
+
+  return true;
+}
+
+euler262();
+```
+
+</div>
+
+
+
+</section>
+
+## Solution
+<section id='solution'>
+
+```js
+// solution required
+```
+
+</section>