From 574269661d46d7a0c3b44666ec480cd73b191267 Mon Sep 17 00:00:00 2001
From: koronya <koronya@hanmail.net>
Date: Sun, 5 Apr 2026 22:10:06 +0900
Subject: [PATCH] [JS][7kyu] Vampire Numbers

---
 codewars/7kyu/vampire-numbers/koronya.js | 34 ++++++++++++++++++++++++
 1 file changed, 34 insertions(+)
 create mode 100644 codewars/7kyu/vampire-numbers/koronya.js

diff --git a/codewars/7kyu/vampire-numbers/koronya.js b/codewars/7kyu/vampire-numbers/koronya.js
new file mode 100644
index 000000000..e4b0539f6
--- /dev/null
+++ b/codewars/7kyu/vampire-numbers/koronya.js
@@ -0,0 +1,34 @@
+// [JS][7kyu] Vampire Numbers
+// vampire-numbers
+// https://www.codewars.com/kata/54d418bd099d650fa000032d/train/javascript
+
+const getResult = (numArr) => {
+  const minusCount = numArr.filter((num) => num < 0).length
+  if (minusCount > 0 && minusCount % 2 === 0) {
+    return false
+  }
+  const resultMap = new Map()
+  numArr
+    .map((num) =>
+      String(num)
+        .split('')
+        .map((n) => n.replace(/-/g, '')),
+    )
+    .flat()
+    .sort()
+    .forEach((num) => {
+      resultMap.set(num, (resultMap.get(num) || 0) + 1)
+    })
+  return [...resultMap].map(([key, value]) => `${key}:${value}`).join('+')
+}
+
+const vampireTest = (a, b) => getResult([a, b]) === getResult([a * b])
+
+// vampireTest(21, 6) === true
+// vampireTest(204, 615) === true
+// vampireTest(30, -51) === true
+// vampireTest(-246, -510) === false
+// vampireTest(2947050, 8469153) === true
+// vampireTest(2947051, 8469153) === false
+// vampireTest(0, 0)
+// vampireTest(-246, -510)