From bb7551fadc6608a12121eea875401767f3fcfc8b Mon Sep 17 00:00:00 2001
From: Stevo <stevehuwjohn@gmail.com>
Date: Mon, 8 Apr 2024 14:57:34 +0100
Subject: [PATCH] WIP

---
 src/Sudoku/Extensions/IntArrayExtensions.cs | 12 +++++++-----
 src/Sudoku/Extensions/SpanIntExtensions.cs  | 20 ++++++++++++--------
 src/Sudoku/Generator.cs                     | 10 ++++++----
 3 files changed, 25 insertions(+), 17 deletions(-)

diff --git a/src/Sudoku/Extensions/IntArrayExtensions.cs b/src/Sudoku/Extensions/IntArrayExtensions.cs
index e266b22..f90cc44 100644
--- a/src/Sudoku/Extensions/IntArrayExtensions.cs
+++ b/src/Sudoku/Extensions/IntArrayExtensions.cs
@@ -27,13 +27,15 @@ public static void DumpToConsole(this int[] array, int left = -1, int top = -1)
             }
 
             Console.WriteLine(" │");
-            
-            if (y is 2 or 5)
+
+            if (y is not (2 or 5))
             {
-                SetPosition(left, top, line++);
-            
-                Console.WriteLine("├───────┼───────┼───────┤");
+                continue;
             }
+            
+            SetPosition(left, top, line++);
+            
+            Console.WriteLine("├───────┼───────┼───────┤");
         }
         
         SetPosition(left, top, line);
diff --git a/src/Sudoku/Extensions/SpanIntExtensions.cs b/src/Sudoku/Extensions/SpanIntExtensions.cs
index 3be728f..80e55f2 100644
--- a/src/Sudoku/Extensions/SpanIntExtensions.cs
+++ b/src/Sudoku/Extensions/SpanIntExtensions.cs
@@ -27,12 +27,14 @@ public static bool IsValidSudoku(this Span<int> puzzle)
                     countRow++;
                 }
 
-                if (puzzle[y + x * 9] != 0)
+                if (puzzle[y + x * 9] == 0)
                 {
-                    uniqueColumn.Add(puzzle[y + x * 9]);
-
-                    countColumn++;
+                    continue;
                 }
+                
+                uniqueColumn.Add(puzzle[y + x * 9]);
+
+                countColumn++;
             }
 
             if (uniqueRow.Count < countRow || uniqueColumn.Count < countColumn)
@@ -55,12 +57,14 @@ public static bool IsValidSudoku(this Span<int> puzzle)
                 {
                     for (var y = 0; y < 3; y++)
                     {
-                        if (puzzle[(yO + y) * 9 + xO + x] != 0)
+                        if (puzzle[(yO + y) * 9 + xO + x] == 0)
                         {
-                            uniqueBox.Add(puzzle[(yO + y) * 9 + xO + x]);
-
-                            countBox++;
+                            continue;
                         }
+                        
+                        uniqueBox.Add(puzzle[(yO + y) * 9 + xO + x]);
+
+                        countBox++;
                     }
                 }
 
diff --git a/src/Sudoku/Generator.cs b/src/Sudoku/Generator.cs
index e3b1dc4..ffc4b17 100644
--- a/src/Sudoku/Generator.cs
+++ b/src/Sudoku/Generator.cs
@@ -57,12 +57,14 @@ private void RemoveCells(int[] puzzle, int cellsToRemove)
 
             for (var i = 0; i < 81; i++)
             {
-                if (puzzle[i] == 0)
+                if (puzzle[i] != 0)
                 {
-                    filledCells.Add(i);
-
-                    puzzle[i] = copy[i];
+                    continue;
                 }
+                
+                filledCells.Add(i);
+
+                puzzle[i] = copy[i];
             }
         }
     }