diff --git a/best-time-to-buy-and-sell-stock/GUMUNYEONG.js b/best-time-to-buy-and-sell-stock/GUMUNYEONG.js
new file mode 100644
index 00000000..c5a057ea
--- /dev/null
+++ b/best-time-to-buy-and-sell-stock/GUMUNYEONG.js
@@ -0,0 +1,19 @@
+/**
+ * @param {number[]} prices
+ * @return {number}
+ */
+var maxProfit = function (prices) {
+    let max = 0;
+
+    for (let i = 0; i <= prices.length; i++) {
+        for (let j = i + 1; j <= prices.length; j++) {
+            const profit = prices[j] - prices[i];
+            max = profit > max ? profit : max;
+        }
+    }
+
+    return max;
+};
+
+// TC : O(n^2);
+// SC : O(1);