From 1e7c67314ed35897e04e9d6e237b7cdbbbfb7dc7 Mon Sep 17 00:00:00 2001
From: koronya <koronya@hanmail.net>
Date: Mon, 8 Jun 2026 04:24:37 +0900
Subject: [PATCH] [JS][7kyu] Basic Math (Add or Subtract)

---
 .../basic-math-add-or-subtract/koronya.js     | 21 +++++++++++++++++++
 1 file changed, 21 insertions(+)
 create mode 100644 codewars/7kyu/basic-math-add-or-subtract/koronya.js

diff --git a/codewars/7kyu/basic-math-add-or-subtract/koronya.js b/codewars/7kyu/basic-math-add-or-subtract/koronya.js
new file mode 100644
index 000000000..cbf6b3afd
--- /dev/null
+++ b/codewars/7kyu/basic-math-add-or-subtract/koronya.js
@@ -0,0 +1,21 @@
+// [JS][7kyu] Basic Math (Add or Subtract)
+// basic-math-add-or-subtract
+// https://www.codewars.com/kata/5809b62808ad92e31b000031/train/javascript
+
+const calculate = (str) => {
+  const numbers = str.match(/\d+/g)
+  const words = str.match(/[a-zA-Z]+/g)
+  const arr = numbers.map((num, index) => {
+    const number = Number(num)
+    if (index === 0 || words[index - 1] === 'plus') {
+      return number
+    }
+    return -1 * number
+  })
+
+  return String(arr.reduce((acc, curr) => acc + curr, 0))
+}
+
+calculate('1plus2plus3plus4') === '10'
+calculate('1minus2minus3minus4') === '-8'
+calculate('10plus20plus30minus40') === '20'