organize ll methods

201flaviosilva · May 23, 2023 · b24936c · b24936c
1 parent fdf8f20
commit b24936c
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Showing 2 changed files with 76 additions and 77 deletions.
diff --git a/src/DataStructures/LinkedList.js b/src/DataStructures/LinkedList.js
@@ -57,6 +57,19 @@ export class LinkedList {
 		return true;
 	}
 
+	// ADD a new value to the START of the list
+	unshift(value) {
+		const newNode = new Node(value);
+		newNode.next = this.head;
+		this.head = newNode;
+
+		if (!this.tail) this.tail = newNode;
+
+		this.size++;
+
+		return this;
+	}
+
 	// ADD a new value to the END of the list
 	push(value) {
 		const newNode = new Node(value);
@@ -72,23 +85,23 @@ export class LinkedList {
 		return this;
 	}
 
-	// ADD a new value to the START of the list
-	unshift(value) {
-		const newNode = new Node(value);
-		newNode.next = this.head;
-		this.head = newNode;
+	// ADD a new value to the given index of the list
+	insert(value, index) {
+		return this;
+	}
 
-		if (!this.tail) this.tail = newNode;
+	// REMOVE a value to the START of the list
+	shift() {
+		if (!this.size) return undefined;
 
-		this.size++;
+		const removedValue = this.head.value;
 
-		return this;
-	}
+		this.head = this.head.next;
 
+		this.size--;
 
-	// ADD a new value to the given index of the list
-	insert(value, index) {
-		return this;
+		if (this.size === 0) this.clear();
+		return removedValue;
 	}
 
 	// REMOVE a value from the END of the list
@@ -111,20 +124,6 @@ export class LinkedList {
 		return temp.value;
 	}
 
-	// REMOVE a value to the START of the list
-	shift() {
-		if (!this.size) return undefined;
-
-		const removedValue = this.head.value;
-
-		this.head = this.head.next;
-
-		this.size--;
-
-		if (this.size === 0) this.clear();
-		return removedValue;
-	}
-
 	// REMOVE a value in the given index of the list
 	remove(value, index) {
 		return this;

diff --git a/tests/DataStructures/LinkedList.test.js b/tests/DataStructures/LinkedList.test.js
@@ -120,26 +120,6 @@ describe("LinkedList.js", () => {
 			});
 		});
 
-		describe("push()", () => {
-			it("adds items to the end of the linked list", () => {
-				const ll = new LinkedList(100);
-
-				expect(ll.push(50)).toBeInstanceOf(LinkedList);
-				expect(ll.size).toBe(2);
-				expect(ll.head.value).toBe(100);
-				expect(ll.head.next.value).toBe(50);
-				expect(ll.tail.value).toBe(50);
-
-				ll.push(25);
-				expect(ll.size).toBe(3);
-				expect(ll.head.value).toBe(100);
-				expect(ll.head.next.next.value).toBe(25);
-				expect(ll.tail.value).toBe(25);
-
-				expect(ll.toArray()).toEqual([100, 50, 25]);
-			});
-		});
-
 		describe("unshift()", () => {
 			it("should add a new element at the start", () => {
 				const ll = new LinkedList(0);
@@ -179,45 +159,23 @@ describe("LinkedList.js", () => {
 			});
 		});
 
-		describe("pop()", () => {
-			it("remove the last element from the linked list", () => {
+		describe("push()", () => {
+			it("adds items to the end of the linked list", () => {
 				const ll = new LinkedList(100);
-				ll.push(50);
-				ll.push(25);
-				ll.push(13);
 
-				expect(ll.pop()).toBe(13);
-				expect(ll.size).toBe(3);
-				expect(ll.head.value).toBe(100);
-				expect(ll.tail.value).toBe(25);
-				expect(ll.tail.next).toBe(null);
-				expect(ll.toArray()).toEqual([100, 50, 25]);
-
-				expect(ll.pop()).toBe(25);
+				expect(ll.push(50)).toBeInstanceOf(LinkedList);
 				expect(ll.size).toBe(2);
 				expect(ll.head.value).toBe(100);
+				expect(ll.head.next.value).toBe(50);
 				expect(ll.tail.value).toBe(50);
-				expect(ll.tail.next).toBe(null);
-				expect(ll.toArray()).toEqual([100, 50]);
 
-				expect(ll.pop()).toBe(50);
-				expect(ll.size).toBe(1);
+				ll.push(25);
+				expect(ll.size).toBe(3);
 				expect(ll.head.value).toBe(100);
-				expect(ll.tail.value).toBe(100);
-				expect(ll.tail.next).toBe(null);
-				expect(ll.toArray()).toEqual([100]);
-
-				expect(ll.pop()).toBe(100);
-				expect(ll.size).toBe(0);
-				expect(ll.head).toBe(null);
-				expect(ll.tail).toBe(null);
-				expect(ll.toArray()).toEqual([]);
+				expect(ll.head.next.next.value).toBe(25);
+				expect(ll.tail.value).toBe(25);
 
-				expect(ll.pop()).toBe(undefined);
-				expect(ll.size).toBe(0);
-				expect(ll.head).toBe(null);
-				expect(ll.tail).toBe(null);
-				expect(ll.toArray()).toEqual([]);
+				expect(ll.toArray()).toEqual([100, 50, 25]);
 			});
 		});
 
@@ -257,6 +215,48 @@ describe("LinkedList.js", () => {
 			});
 		});
 
+		describe("pop()", () => {
+			it("remove the last element from the linked list", () => {
+				const ll = new LinkedList(100);
+				ll.push(50);
+				ll.push(25);
+				ll.push(13);
+
+				expect(ll.pop()).toBe(13);
+				expect(ll.size).toBe(3);
+				expect(ll.head.value).toBe(100);
+				expect(ll.tail.value).toBe(25);
+				expect(ll.tail.next).toBe(null);
+				expect(ll.toArray()).toEqual([100, 50, 25]);
+
+				expect(ll.pop()).toBe(25);
+				expect(ll.size).toBe(2);
+				expect(ll.head.value).toBe(100);
+				expect(ll.tail.value).toBe(50);
+				expect(ll.tail.next).toBe(null);
+				expect(ll.toArray()).toEqual([100, 50]);
+
+				expect(ll.pop()).toBe(50);
+				expect(ll.size).toBe(1);
+				expect(ll.head.value).toBe(100);
+				expect(ll.tail.value).toBe(100);
+				expect(ll.tail.next).toBe(null);
+				expect(ll.toArray()).toEqual([100]);
+
+				expect(ll.pop()).toBe(100);
+				expect(ll.size).toBe(0);
+				expect(ll.head).toBe(null);
+				expect(ll.tail).toBe(null);
+				expect(ll.toArray()).toEqual([]);
+
+				expect(ll.pop()).toBe(undefined);
+				expect(ll.size).toBe(0);
+				expect(ll.head).toBe(null);
+				expect(ll.tail).toBe(null);
+				expect(ll.toArray()).toEqual([]);
+			});
+		});
+
 		describe("toArray()", () => {
 			it("should return an array with the values of the linked list", () => {
 				const ll = new LinkedList(0);