Add solution #2629

Author: JoshCrozier

README.md

@@ -363,6 +363,7 @@
 2535|[Difference Between Element Sum and Digit Sum of an Array](./2535-difference-between-element-sum-and-digit-sum-of-an-array.js)|Easy|
 2618|[Check if Object Instance of Class](./2618-check-if-object-instance-of-class.js)|Medium|
 2619|[Array Prototype Last](./2619-array-prototype-last.js)|Easy|
+2629|[Function Composition](./2629-function-composition.js)|Easy|
 3392|[Count Subarrays of Length Three With a Condition](./3392-count-subarrays-of-length-three-with-a-condition.js)|Easy|
 3396|[Minimum Number of Operations to Make Elements in Array Distinct](./3396-minimum-number-of-operations-to-make-elements-in-array-distinct.js)|Easy|
 3397|[Maximum Number of Distinct Elements After Operations](./3397-maximum-number-of-distinct-elements-after-operations.js)|Medium|

solutions/2629-function-composition.js

@@ -0,0 +1,23 @@
+/**
+ * 2629. Function Composition
+ * https://leetcode.com/problems/function-composition/
+ * Difficulty: Easy
+ *
+ * Given an array of functions [f1, f2, f3, ..., fn], return a new function fn that is the function
+ * composition of the array of functions.
+ *
+ * The function composition of [f(x), g(x), h(x)] is fn(x) = f(g(h(x))).
+ *
+ * The function composition of an empty list of functions is the identity function f(x) = x.
+ *
+ * You may assume each function in the array accepts one integer as input and returns one integer
+ * as output.
+ */
+
+/**
+ * @param {Function[]} functions
+ * @return {Function}
+ */
+var compose = function(functions) {
+  return x => functions.reduceRight((result, fn) => fn(result), x);
+};