From e843e149fa892c9e3067f2f35f08a41851ccd5de Mon Sep 17 00:00:00 2001
From: jackfiled <xcrenchangjun@outlook.com>
Date: Sun, 15 Dec 2024 12:13:17 +0800
Subject: [PATCH] 20241215 finished.

---
 src/problem/mod.rs                            |  2 +
 .../p1338_reduce_array_size_to_the_half.rs    | 54 +++++++++++++++++++
 2 files changed, 56 insertions(+)
 create mode 100644 src/problem/p1338_reduce_array_size_to_the_half.rs

diff --git a/src/problem/mod.rs b/src/problem/mod.rs
index 7b80f64..a71aa1a 100644
--- a/src/problem/mod.rs
+++ b/src/problem/mod.rs
@@ -370,3 +370,5 @@ mod p2931_maximum_spending_after_buying_items;
 mod p3264_final_array_state_after_k_multiplication_operations_i;
 
 mod p3266_final_array_state_after_k_multiplication_operations_ii;
+
+mod p1338_reduce_array_size_to_the_half;
diff --git a/src/problem/p1338_reduce_array_size_to_the_half.rs b/src/problem/p1338_reduce_array_size_to_the_half.rs
new file mode 100644
index 0000000..b94b957
--- /dev/null
+++ b/src/problem/p1338_reduce_array_size_to_the_half.rs
@@ -0,0 +1,54 @@
+/**
+ * [1338] Reduce Array Size to The Half
+ */
+pub struct Solution {}
+
+// submission codes start here
+use std::collections::BinaryHeap;
+use std::collections::HashMap;
+
+impl Solution {
+    pub fn min_set_size(arr: Vec<i32>) -> i32 {
+        let mut map = HashMap::new();
+
+        for &i in arr.iter() {
+            let entry = map.entry(i).or_insert(0);
+            *entry += 1;
+        }
+
+        let mut heap = BinaryHeap::with_capacity(map.len());
+
+        for (_, v) in map {
+            heap.push(v);
+        }
+
+        let mut result = 0;
+        let mut count = arr.len();
+        let target = count / 2;
+
+        while count > target {
+            if let Some(head) = heap.pop() {
+                count -= head;
+                result += 1;
+            }
+        }
+
+        result
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_1338() {
+        assert_eq!(
+            2,
+            Solution::min_set_size(vec![3, 3, 3, 3, 5, 5, 5, 2, 2, 7])
+        );
+        assert_eq!(1, Solution::min_set_size(vec![7, 7, 7, 7, 7, 7]));
+    }
+}