From 3567508aa5136f9fb27cb66869d072644ad68988 Mon Sep 17 00:00:00 2001
From: yanglbme <szuyanglb@outlook.com>
Date: Thu, 5 Jun 2025 06:30:55 +0800
Subject: [PATCH] feat: add solutions to lc problem: No.3442

No.3442.Maximum Difference Between Even and Odd Frequency I
---
 .../README.md                                 | 45 +++++++++++++++++++
 .../README_EN.md                              | 45 +++++++++++++++++++
 .../Solution.cs                               | 17 +++++++
 .../Solution.rs                               | 18 ++++++++
 4 files changed, 125 insertions(+)
 create mode 100644 solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/Solution.cs
 create mode 100644 solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/Solution.rs

diff --git a/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/README.md b/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/README.md
index 7dede5e81a526..0b196fab0a495 100644
--- a/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/README.md	
+++ b/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/README.md	
@@ -187,6 +187,51 @@ function maxDifference(s: string): number {
 }
 ```
 
+#### Rust
+
+```rust
+impl Solution {
+    pub fn max_difference(s: String) -> i32 {
+        let mut cnt = [0; 26];
+        for c in s.bytes() {
+            cnt[(c - b'a') as usize] += 1;
+        }
+        let mut a = 0;
+        let mut b = 1 << 30;
+        for &v in cnt.iter() {
+            if v % 2 == 1 {
+                a = a.max(v);
+            } else if v > 0 {
+                b = b.min(v);
+            }
+        }
+        a - b
+    }
+}
+```
+
+#### C#
+
+```cs
+public class Solution {
+    public int MaxDifference(string s) {
+        int[] cnt = new int[26];
+        foreach (char c in s) {
+            ++cnt[c - 'a'];
+        }
+        int a = 0, b = 1 << 30;
+        foreach (int v in cnt) {
+            if (v % 2 == 1) {
+                a = Math.Max(a, v);
+            } else if (v > 0) {
+                b = Math.Min(b, v);
+            }
+        }
+        return a - b;
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->
diff --git a/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/README_EN.md b/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/README_EN.md
index 806b2acbdee19..8d794fabbb91f 100644
--- a/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/README_EN.md	
+++ b/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/README_EN.md	
@@ -185,6 +185,51 @@ function maxDifference(s: string): number {
 }
 ```
 
+#### Rust
+
+```rust
+impl Solution {
+    pub fn max_difference(s: String) -> i32 {
+        let mut cnt = [0; 26];
+        for c in s.bytes() {
+            cnt[(c - b'a') as usize] += 1;
+        }
+        let mut a = 0;
+        let mut b = 1 << 30;
+        for &v in cnt.iter() {
+            if v % 2 == 1 {
+                a = a.max(v);
+            } else if v > 0 {
+                b = b.min(v);
+            }
+        }
+        a - b
+    }
+}
+```
+
+#### C#
+
+```cs
+public class Solution {
+    public int MaxDifference(string s) {
+        int[] cnt = new int[26];
+        foreach (char c in s) {
+            ++cnt[c - 'a'];
+        }
+        int a = 0, b = 1 << 30;
+        foreach (int v in cnt) {
+            if (v % 2 == 1) {
+                a = Math.Max(a, v);
+            } else if (v > 0) {
+                b = Math.Min(b, v);
+            }
+        }
+        return a - b;
+    }
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->
diff --git a/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/Solution.cs b/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/Solution.cs
new file mode 100644
index 0000000000000..e6a7e73ec0819
--- /dev/null
+++ b/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/Solution.cs	
@@ -0,0 +1,17 @@
+public class Solution {
+    public int MaxDifference(string s) {
+        int[] cnt = new int[26];
+        foreach (char c in s) {
+            ++cnt[c - 'a'];
+        }
+        int a = 0, b = 1 << 30;
+        foreach (int v in cnt) {
+            if (v % 2 == 1) {
+                a = Math.Max(a, v);
+            } else if (v > 0) {
+                b = Math.Min(b, v);
+            }
+        }
+        return a - b;
+    }
+}
diff --git a/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/Solution.rs b/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/Solution.rs
new file mode 100644
index 0000000000000..751cc12a81a50
--- /dev/null
+++ b/solution/3400-3499/3442.Maximum Difference Between Even and Odd Frequency I/Solution.rs	
@@ -0,0 +1,18 @@
+impl Solution {
+    pub fn max_difference(s: String) -> i32 {
+        let mut cnt = [0; 26];
+        for c in s.bytes() {
+            cnt[(c - b'a') as usize] += 1;
+        }
+        let mut a = 0;
+        let mut b = 1 << 30;
+        for &v in cnt.iter() {
+            if v % 2 == 1 {
+                a = a.max(v);
+            } else if v > 0 {
+                b = b.min(v);
+            }
+        }
+        a - b
+    }
+}