Day3. Start Algorithm

704. Binary Search/704. Binary Search.csproj

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+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <RootNamespace>_704._Binary_Search</RootNamespace>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

704. Binary Search/Program.cs

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+namespace _704._Binary_Search
+{
+    internal class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine(new Solution().Search(new int[] { -1, 0, 3, 5, 9, 12 }, 13));
+        }
+    }
+}

704. Binary Search/Solution.cs

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+namespace _704._Binary_Search;
+
+public class Solution
+{
+    public int Search(int[] nums, int target)
+    {
+        int l = -1;
+        int r = nums.Length;
+        while (l < r - 1)
+        {
+            int i = l + (r - l) / 2;
+            int cur = nums[i];
+            if (cur == target)
+                return i;
+            if (cur > target)
+                r = i;
+            else
+                l = i;
+        }
+        return -1;
+    }
+}