From 728f44ab38a42df1cb763f828957ea3f2a4e131d Mon Sep 17 00:00:00 2001
From: gikf <60067306+gikf@users.noreply.github.com>
Date: Wed, 3 Mar 2021 18:32:51 +0100
Subject: [PATCH] fix: clarify case for already placed valid number (#41225)

---
 .../sudoku-solver.md                          | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/curriculum/challenges/english/06-quality-assurance/quality-assurance-projects/sudoku-solver.md b/curriculum/challenges/english/06-quality-assurance/quality-assurance-projects/sudoku-solver.md
index dde3301c58..849606c2e0 100644
--- a/curriculum/challenges/english/06-quality-assurance/quality-assurance-projects/sudoku-solver.md
+++ b/curriculum/challenges/english/06-quality-assurance/quality-assurance-projects/sudoku-solver.md
@@ -202,6 +202,25 @@ async (getUserInput) => {
 };
 ```
 
+If `value` submitted to `/api/check` is already placed in `puzzle` on that `coordinate`, the returned value will be an object containing a `valid` property with `true` if `value` is not conflicting.
+
+```js
+async (getUserInput) => {
+  const input =
+  '..9..5.1.85.4....2432......1...69.83.9.....6.62.71...9......1945....4.37.4.3..6..';
+  const coordinate = 'C3';
+  const value = '2';
+  const data = await fetch(getUserInput('url') + '/api/check', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ puzzle: input, coordinate, value })
+  });
+  const parsed = await data.json();
+  assert.property(parsed, 'valid');
+  assert.isTrue(parsed.valid);
+};
+```
+
 If the puzzle submitted to `/api/check` contains values which are not numbers or periods, the returned value will be `{ error: 'Invalid characters in puzzle' }`
 
 ```js