Day5

240. Search a 2D Matrix II/240. Search a 2D Matrix II.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <RootNamespace>_240._Search_a_2D_Matrix_II</RootNamespace>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

240. Search a 2D Matrix II/Program.cs

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+namespace _240._Search_a_2D_Matrix_II
+{
+    internal class Program
+    {
+        static void Main(string[] args)
+        {
+            int[][] matrix = new int[][] { new int[] { 1, 1,1,1 } };
+            Console.WriteLine(new Solution().SearchMatrix(matrix, 2));
+        }
+    }
+}

240. Search a 2D Matrix II/Solution.cs

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+namespace _240._Search_a_2D_Matrix_II;
+
+public class Solution
+{
+    public bool SearchMatrix(int[][] matrix, int target)
+    {
+        for (int row = 0; row < matrix.Length; row++)
+        {
+            int column = SearchInsert((i) => matrix[row][i], matrix[row].Length, target);
+            if (column < matrix[row].Length && matrix[row][column] == target)
+                return true;
+        }
+        return false;
+    }
+
+    private int SearchInsert(Func<int, int> getByIndex, int len, int target)
+    {
+        int l = -1;
+        int r = len;
+        while (l != r - 1)
+        {
+            int i = (r + l) / 2;
+            if (getByIndex(i) >= target)
+                r = i;
+            else
+                l = i;
+        }
+        return l + 1;
+    }
+}