Remove a val in arr and return the length of remaining values

removeelement/index.test.js

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+const { expect } = require("chai")
+const removeElement = require("./solution");
+
+describe("remove element", () => {
+    it("should remove an element and return its length", () => {
+        const result = removeElement([3, 2, 1, 3], 3);
+        expect(result).to.equal(2);
+    });
+
+    it("returns 4 when val is not in an arr below", () => {
+        const result = removeElement([3, 2, 1, 3], 5);
+        expect(result).to.equal(4);
+    });
+
+    it("should return 0 when arr is empty", () => {
+        const result = removeElement([], 3);
+        expect(result).to.equal(0);
+    });
+});

removeelement/question.txt

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+-> Given an array arr and a value val, 
+-> remove all instances of that value in-place 
+-> and return the new length.
+
+-> Do not allocate extra space for another array, 
+-> you must do this by modifying the input array in-place with O(1) extra memory.
+
+-> The order of elements can be changed. 
+-> It doesn't matter what you leave beyond the new length.
+
+Example:-
+
+-> Given arr = [3,2,2,3], val = 3,
+-> Your function should return length = 2
+-> with the first two elements of arr being 2.
+-> It doesn't matter what you leave beyond the returned length.

removeelement/solution.js

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+const removeElement = (arr, val) => {
+    // initialize count to zero
+    let counts = 0;
+    // loop through the arra
+    for (let i = 0; i < arr.length; i++) {
+        /**
+         * check if num is not equal to val
+         * then increment the number of counts
+         * but assigining its num values
+         */
+        if (arr[i] != val) {
+            arr[counts++] = arr[i]
+        }
+    }
+    // return our counts
+    return counts;
+}
+
+exports = module.exports = removeElement;