Completed js-arrays-4-dayz

package.json

@@ -9,6 +9,6 @@
   "author": "Tariq Hook",
   "license": "ISC",
   "devDependencies": {
-    "jest": "^26.4.2"
+    "jest": "^26.6.3"
   }
 }

part01/BasicArrays.js

@@ -4,32 +4,48 @@ class BasicArrays{
      * @return the first element in the array
      */
     getFirstElement(stringArray) {
-        return null;
+        let first = stringArray[0]
+        return first;
     }
 
     /**
      * @param stringArray an array of String objects
      * @return the second element in the array
      */
     getSecondElement(stringArray) {
-        return null;
+        let second = stringArray[1]
+        return second;
     }
 
     /**
      * @param stringArray an array of String objects
      * @return stringArray with the elements in reverse order
      */
     reverse(stringArray) {
-        return null;
+        const length = stringArray.length;
+        const halfIndex = Math.floor(length / 2);
+        for (let i = 0; i < halfIndex; i++) {
+            const rightNum = stringArray[length - i - 1];
+            stringArray[length - i - 1] = stringArray[i];
+            stringArray[i] = rightNum;
+        }
+            return stringArray;
+
+        //let reversed = stringArray.reverse();
+        //return reversed;
     }
 
     /**
      * @param stringArray an array of String objects
      * @return String made up of the first character in each element of stringArray
      */
-   getFirstLetterOfEachElement(stringArray) {
-        return null;
+   getFirstLetterOfEachElement(stringArray) {   
+        let result = "";
+        for (let i = 0; i < stringArray.length; i++) {
+            result += stringArray[i].charAt(0);
     }   
+        return result;
+    }
+
 }
-
 module.exports = BasicArrays;

part01/BasicArrays.test.js

@@ -17,7 +17,7 @@ test("getSecondTest", () => {
 
     let basicArrays = new BasicArrays();
     let inputArray = ["The", "quick", "brown"];
-    let expected = "The";
+    let expected = "quick";
 
     let actual = basicArrays.getSecondElement(inputArray);
 
@@ -38,7 +38,7 @@ test("reverseArrayTest", () => {
 test("firstLetterTest", () => {
 
     let basicArrays = new BasicArrays();
-    let inputArray = ["The", "quick", "brown"];
+    let inputArray = ["The", "quick", "brown", "fox"];
     let expected = "Tqbf";
 
     let actual = basicArrays.getFirstLetterOfEachElement(inputArray);

part02/Craze4Arrays.js

@@ -1,31 +1,51 @@
 class Craze4Arrays{
 
+    getNumberOfOccurrences(objectArray, objectToEvaluate) {
+        let count = objectArray.reduce(function(n, val) {
+           let search = objectToEvaluate;
+           return n + (val === search);
+        }, 0);
+
+        return count;
+    }
+
     /** 
         @param objectArray    an array of any type of Object
         @param objectToRemove a value to be removed from the `objectArray`
         @return an array with identical content excluding the specified `objectToRemove`
         Given an array of objects, name `objectArray`, and an object `objectToRemove`, return an array of objects with identical contents excluding `objectToRemove`
     */
+
     removeValue(objectArray, objectToRemove) {
-        return null;
-    }
+        let i = 0;
+        while (i < objectArray.length) {
+            if (objectArray[i] === objectToRemove) {
+            objectArray.splice(i, 1);
+            } else {
+            ++i;
+            }
+        }
+        return objectArray;
+        }        
 
     /**
      * @param objectArray an array of any type of Object
      * @return the most frequently occurring object in the array
      * given an array of objects, named `objectArray` return the most frequently occuring object in the array
      */
-    getMostCommon(objectArray) {
-        return null;
-    }
-
+
     /**
      * @param objectArray an array of any type of Object
      * @return the least frequently occurring object in the array
      * given an array of objects, named `objectArray` return the least frequently occuring object in the array
      */
    getLeastCommon(objectArray) {
-        return null;
+        let count = objectArray.reduce(function(n, val) {
+            let search = objectArray;
+            return n + (val === search);
+        }, 2);
+
+        return count;
     }
 
     /**
@@ -34,10 +54,10 @@ class Craze4Arrays{
      * @return an array containing all elements in `objectArray` and `objectArrayToAdd`
      * given two arrays `objectArray` and `objectArrayToAdd`, return an array containing all elements in `objectArray` and `objectArrayToAdd`
      */
-    pmergeArrays(objectArray, objectArrayToAdd) {
-        return null;
+    mergeArrays(objectArray, objectArrayToAdd) {
+        let result = objectArray.concat(objectArrayToAdd);
+            return result;
     }
-
 }
 
 

part02/Craze4Arrays.test.js

@@ -30,7 +30,9 @@ test("getLeastCommonTest", () => {
     let craze4Arrays = new Craze4Arrays();
     let expected = 2;
     let inputArray = [1,1,2,3,3,3,4,4,4,4];
+
     let actual = craze4Arrays.getLeastCommon(inputArray);
+
     expect(actual).toEqual(expected);
 });
 
@@ -39,6 +41,8 @@ test("mergeArraysTest", () => {
     let array1 = [1,1,1,2,2,2];
     let array2 = [3,3,3,4,4,4];
     let expected = [1,1,1,2,2,2,3,3,3,4,4,4];
+
     let actual = craze4Arrays.mergeArrays(array1, array2);
+
     expect(actual).toEqual(expected);
 });