Tasks done

Exercises/1-remove.js

@@ -1,7 +1,6 @@
 'use strict';
 
-const removeElement = (array, item) => {
-  // Remove item from array modifying original array
-};
+const removeElement = (array, item) =>
+  (array.includes(item) ? array.splice(array.indexOf(item), 1) : array);
 
 module.exports = { removeElement };

Exercises/2-elements.js

@@ -1,7 +1,8 @@
 'use strict';
 
 const removeElements = (array, ...items) => {
-  // Remove multiple items from array modifying original array
+  for (const item of items)
+    array.includes(item) ? array.splice(array.indexOf(item), 1) : array;
 };
 
 module.exports = { removeElements };

Exercises/3-unique.js

@@ -3,6 +3,14 @@
 // Create and return a new array without duplicate elements
 // Don't modify initial array
 
-const unique = array => [];
+const unique = array => {
+  const na = [];
+
+  array.forEach(i => {
+    if (!na.includes(i)) na.push(i);
+  });
+
+  return na;
+};
 
 module.exports = { unique };

Exercises/4-difference.js

@@ -3,6 +3,14 @@
 // Find difference of two arrays
 // elements from array1 that are not includes in array2
 
-const difference = (array1, array2) => [];
+const difference = (array1, array2) => {
+  const na = [];
+
+  array1.forEach(i => {
+    if (!array2.includes(i)) na.push(i);
+  });
+
+  return na;
+};
 
 module.exports = { difference };