From 201e4b52b2753240dcd2daa8c90064c27fe28cfa Mon Sep 17 00:00:00 2001
From: Hidemichi Shimura <hidemichi.shimura@gmail.com>
Date: Fri, 30 Dec 2022 20:34:33 -0800
Subject: [PATCH 1/2] solve 1636. Sort Array by Increasing Frequency

---
 1636.sort-array-by-increasing-frequency.js | 35 ++++++++++++++++++++++
 1 file changed, 35 insertions(+)
 create mode 100644 1636.sort-array-by-increasing-frequency.js

diff --git a/1636.sort-array-by-increasing-frequency.js b/1636.sort-array-by-increasing-frequency.js
new file mode 100644
index 00000000..d0f8b004
--- /dev/null
+++ b/1636.sort-array-by-increasing-frequency.js
@@ -0,0 +1,35 @@
+/* URL of this problem
+ * https://leetcode.com/problems/sort-array-by-increasing-frequency/description/
+ *
+ * @param {number[]} nums
+ * @return {number[]}
+ */
+
+var frequencySort = function(nums) {
+    const UniqueNums = [...new Set(nums)];
+    const SortedNums = [];
+
+    // Make an array of each unique number and push the array to SortedNums
+    for (let i = 0; i < UniqueNums.length; i++) {
+        const CurrNums = nums.filter(num => num === UniqueNums[i]);
+
+        SortedNums.push(CurrNums);
+    }
+    SortedNums.sort((currNums, nextNums) => {
+        const CurrLen = currNums.length;
+        const NextLen = nextNums.length;
+        const CurrNum = currNums[0];
+        const NextNum = nextNums[0];
+        
+        // Sort the arrays in a descending order by its number if the arrays have the same occurrence
+        if (CurrLen === NextLen) {
+            return NextNum - CurrNum;
+        }
+        // Sort the arrays in an ascending order by occurrence
+        return CurrLen - NextLen;
+    });
+    
+    return SortedNums.flat();
+};
+
+module.exports = frequencySort;
\ No newline at end of file

From 05fae689c73501a8d5dccd6af52f932e6f15952b Mon Sep 17 00:00:00 2001
From: Hidemichi Shimura <hidemichi.shimura@gmail.com>
Date: Fri, 30 Dec 2022 20:34:55 -0800
Subject: [PATCH 2/2] test function frequencySort

---
 frequencySort.test.js | 14 ++++++++++++++
 1 file changed, 14 insertions(+)
 create mode 100644 frequencySort.test.js

diff --git a/frequencySort.test.js b/frequencySort.test.js
new file mode 100644
index 00000000..a25218a7
--- /dev/null
+++ b/frequencySort.test.js
@@ -0,0 +1,14 @@
+const frequencySort = require("./1636.sort-array-by-increasing-frequency");
+
+test("Return the array sorted by increasing frequency and decreasing value for the same frequency", () => {
+    expect(frequencySort([1,1,2,2,2,3])).toEqual([3,1,1,2,2,2]);
+});
+
+test("Return the array with negative values sorted by increasing frequency and decreasing value for the same frequency", () => {
+    expect(frequencySort([-1,1,-6,4,5,-6,1,4,1])).toEqual([5,-1,4,4,-6,-6,1,1,1]);
+});
+
+test("Return the array with Infinity and -Infinity sorted by increasing frequency and decreasing value for the same frequency", () => {
+    expect(frequencySort([1,1,1,-Infinity,-Infinity,Infinity,Infinity]))
+    .toEqual([Infinity,Infinity,-Infinity,-Infinity,1,1,1]);
+});
\ No newline at end of file