From ce9c5ca5d04851a4a905022d6708daadf6b4c7fc Mon Sep 17 00:00:00 2001
From: chayan das <dasshuvo817@gmail.com>
Date: Wed, 16 Jul 2025 22:12:28 +0530
Subject: [PATCH] Create 3201. Find the Maximum Length of Valid Subsequence I

---
 ... the Maximum Length of Valid Subsequence I | 32 +++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 3201. Find the Maximum Length of Valid Subsequence I

diff --git a/3201. Find the Maximum Length of Valid Subsequence I b/3201. Find the Maximum Length of Valid Subsequence I
new file mode 100644
index 0000000..6e3dab9
--- /dev/null
+++ b/3201. Find the Maximum Length of Valid Subsequence I	
@@ -0,0 +1,32 @@
+class Solution {
+public:
+    int maximumLength(vector<int>& nums) {
+        int allev = 0, allodd = 0, oddev = 0;
+
+        // Count total even and odd numbers
+        for (int i = 0; i < nums.size(); i++) {
+            if (nums[i] % 2 == 0) {
+                allev++;
+            } else {
+                allodd++;
+            }
+        }
+
+        // Count longest alternating odd-even subsequence
+        bool expectOdd = true;
+        bool expectEven = true;
+        for (int i = 0; i < nums.size(); i++) {
+            if (nums[i] % 2 == 0 && expectEven) {
+                oddev++;
+                expectEven = false;
+                expectOdd = true;
+            } else if (nums[i] % 2 != 0 && expectOdd) {
+                oddev++;
+                expectOdd = false;
+                expectEven = true;
+            }
+        }
+
+        return max({allev, allodd, oddev});
+    }
+};