Created Files 1941,2626,2629,2634,2635,2703 and 2704 in Javascript

javascript/1941-check-if-all-characters-have-equal-number-of-occurrences.js

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+/**
+ * @param {string} s
+ * @return {boolean}
+ */
+var areOccurrencesEqual = function (s) {
+    let arr = []
+    for (i = 0; i < s.length; i++) {
+        let count = 0;
+        for (j = 0; j < s.length; j++) {
+            if (s[i] == s[j]) {
+                if (i > j) {
+                    break;
+                }
+                count++
+            }
+        }
+        if (count != 0) {
+            arr.push(count)
+        }
+    }
+    let set = new Set(arr)
+    return set.size == 1
+};

javascript/2626-array-reduce-transformation.js

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+/**
+ * @param {number[]} nums
+ * @param {Function} fn
+ * @param {number} init
+ * @return {number}
+ */
+var reduce = function (nums, fn, init) {
+    var val = init;
+    for (let i = 0; i < nums.length; i++) {
+        val = fn(val, nums[i])
+    }
+    return val;
+};
+
+
+var reduce = function (nums, fn, init) {
+
+    for (let i = 0; i < nums.length; i++) {
+        init = fn(init, nums[i])
+    }
+    return init
+};

javascript/2629-function-composition.js

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+/**
+ * @param {Function[]} functions
+ * @return {Function}
+ */
+var compose = function (functions) {
+    return function (x) {
+        if (functions.length === 0) {
+            return x;
+        }
+        var result = x;
+        for (var i = functions.length - 1; i >= 0; i--) {
+            result = functions[i](result);
+        }
+
+        return result;
+    }
+};
+
+/**
+ * const fn = compose([x => x + 1, x => 2 * x])
+ * fn(4) // 9
+ */

javascript/2634-filter-elements-from-array.js

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+/**
+ * @param {number[]} arr
+ * @param {Function} fn
+ * @return {number[]}
+ */
+var filter = function (arr, fn) {
+    const result = arr.filter(fn)
+    return result
+};

javascript/2635-apply-transform-over-each-element-in-array.js

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+/**
+ * @param {number[]} arr
+ * @param {Function} fn
+ * @return {number[]}
+ */
+var map = function (arr, fn) {
+    return arr.map((element, index) => fn(element, index));
+};

javascript/2703-return-length-of-arguments-passed.js

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+/**
+ * @param {...(null|boolean|number|string|Array|Object)} args
+ * @return {number}
+ */
+var argumentsLength = function (...args) {
+    return args.length;
+};
+
+/**
+ * argumentsLength(1, 2, 3); // 3
+ */

javascript/2704-to-be-or-not-to-be.js

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+/**
+ * @param {string} val
+ * @return {Object}
+ */
+var expect = function (val) {
+    return {
+        toBe: (val2) => {
+            if (val !== val2) throw new Error("Not Equal");
+            else return true;
+        },
+        notToBe: (val2) => {
+            if (val === val2) throw new Error("Equal");
+            else return true;
+        }
+    }
+};
+
+/**
+ * expect(5).toBe(5); // true
+ * expect(5).notToBe(5); // throws "Equal"
+ */