@Test
public void testPushToEmptySet() {
SetOfStacks s = new SetOfStacks(2);
assertThat(s.queues(), is(0));
s.push(1);
assertThat(s.size(), is(1));
assertThat(s.queues(), is(1));
assertThat(s.pop(), is(1));
assertThat(s.size(), is(0));
assertThat(s.queues(), is(1));
}
public static void main(String[] args) {
int capacity_per_substack = 5;
SetOfStacks set = new SetOfStacks(capacity_per_substack);
for (int i = 0; i < 34; i++) {
set.push(i);
}
System.out.println("After pushing, current stacks number is: " + set.stacks.size());
/*
for (int i = 0; i < 34; i++) {
System.out.println("Popped " + set.pop());
}
*/
System.out.println(set.popAt(3));
System.out.println(set.popAt(3));
System.out.println(set.popAt(3));
System.out.println(set.popAt(3));
System.out.println(set.popAt(3));
System.out.println(set.popAt(3));
}
@Test
public void testPushElements() {
SetOfStacks s = new SetOfStacks(2);
assertThat(s.queues(), is(0));
s.push(1);
s.push(2);
s.push(3);
s.push(4);
s.push(5);
assertThat(s.size(), is(5));
assertThat(s.queues(), is(3));
assertThat(s.pop(), is(5));
assertThat(s.queues(), is(3));
assertThat(s.pop(), is(4));
assertThat(s.queues(), is(2));
assertThat(s.pop(), is(3));
assertThat(s.queues(), is(2));
assertThat(s.pop(), is(2));
assertThat(s.queues(), is(1));
assertThat(s.size(), is(1));
}
@Test
public void testPopFromEmptySet() {
SetOfStacks s = new SetOfStacks(2);
assertThat(s.pop(), is(MAX_VALUE));
}
/** @param args the command line arguments */
public static void main(String[] args) {
// 1.1
String testStr1 = "World"; // True
String testStr2 = "Hello"; // False
System.out.println("===== 1.1 =====");
System.out.println("Using hash map...");
System.out.print(testStr1 + ": ");
System.out.println(StringAlgorithms.hasAllUniqueChars(testStr1));
System.out.print(testStr2 + ": ");
System.out.println(StringAlgorithms.hasAllUniqueChars(testStr2));
System.out.println("Using no data structures...");
System.out.print(testStr1 + ": ");
System.out.println(StringAlgorithms.hasAllUniqueCharsPrimitive(testStr1));
System.out.print(testStr2 + ": ");
System.out.println(StringAlgorithms.hasAllUniqueCharsPrimitive(testStr2));
System.out.println();
// 1.2
testStr1 = "toastyfresh";
testStr2 = "oatsyetfhrs";
String testStr3 = "hello";
String testStr4 = "helloworlds";
System.out.println("===== 1.2 =====");
System.out.println(testStr1 + " and " + testStr2 + " permutation?");
System.out.println(StringAlgorithms.isPermutation(testStr1, testStr2));
System.out.println(testStr2 + " and " + testStr3 + " permutation?");
System.out.println(StringAlgorithms.isPermutation(testStr2, testStr3));
System.out.println(testStr1 + " and " + testStr4 + " permutation?");
System.out.println(StringAlgorithms.isPermutation(testStr1, testStr4));
System.out.println();
// 1.3
char[] testCharArray = {
'M', 'r', ' ', 'J', 'o', 'h', 'n', ' ', 'S', 'm', 'i', 't', 'h', ' ', ' ', ' ', ' '
};
int size = 13;
String inputString = new String(testCharArray);
String outputString = StringAlgorithms.urlify(testCharArray, size);
System.out.println("===== 1.3 =====");
System.out.println("Input: \"" + inputString + "\"");
System.out.println("Output: \"" + outputString + "\"");
System.out.println();
// 1.4
System.out.println("===== 1.4 =====");
inputString = "Tact Coa";
boolean output = StringAlgorithms.palindromePermutation(inputString);
System.out.println("Input: \"" + inputString + "\"");
System.out.println("Output: " + output);
inputString = "Poop soup";
output = StringAlgorithms.palindromePermutation(inputString);
System.out.println("Input: \"" + inputString + "\"");
System.out.println("Output: " + output);
System.out.println();
// 1.5
System.out.println("===== 1.5 =====");
String inputString1 = "pale";
String inputString2 = "ple";
output = StringAlgorithms.oneAway(inputString1, inputString2);
System.out.println(inputString1 + ", " + inputString2 + "\t-> " + output);
inputString1 = "pales";
inputString2 = "pale";
output = StringAlgorithms.oneAway(inputString1, inputString2);
System.out.println(inputString1 + ", " + inputString2 + "\t-> " + output);
inputString1 = "pale";
inputString2 = "bale";
output = StringAlgorithms.oneAway(inputString1, inputString2);
System.out.println(inputString1 + ", " + inputString2 + "\t-> " + output);
inputString1 = "pale";
inputString2 = "bake";
output = StringAlgorithms.oneAway(inputString1, inputString2);
System.out.println(inputString1 + ", " + inputString2 + "\t-> " + output);
System.out.println();
// 1.6
System.out.println("===== 1.6 =====");
inputString = "aabcccccaaa";
outputString = StringAlgorithms.stringCompression(inputString);
System.out.println("input: " + inputString);
System.out.println("output: " + outputString);
System.out.println();
// 1.7
System.out.println("===== 1.7 =====");
int[][] inputMatrix = {
{20, 18, 22, 20},
{18, 20, 18, 21},
{16, 18, 16, 20},
{25, 24, 22, 24},
};
System.out.println("---- Input ----");
for (int[] inputMatrix1 : inputMatrix) {
for (int j = 0; j < inputMatrix1.length; j++) {
System.out.print(inputMatrix1[j] + " ");
}
System.out.println();
}
int[][] outputMatrix = ArrayAlgorithms.rotateMatrix(inputMatrix);
System.out.println("--- Output ----");
for (int[] outputMatrix1 : outputMatrix) {
for (int j = 0; j < outputMatrix1.length; j++) {
System.out.print(outputMatrix1[j] + " ");
}
System.out.println();
}
System.out.println();
// 1.8
System.out.println("===== 1.8 =====");
int[][] zeroMatrix = {
{0, 1, 1, 1, 0},
{1, 1, 1, 1, 1},
{1, 1, 1, 1, 1},
{0, 1, 1, 1, 0}
};
System.out.println("---- Input ----");
for (int[] inputMatrix1 : zeroMatrix) {
for (int j = 0; j < inputMatrix1.length; j++) {
System.out.print(inputMatrix1[j] + " ");
}
System.out.println();
}
ArrayAlgorithms.zeroMatrix(zeroMatrix);
System.out.println("---- Output ----");
for (int[] inputMatrix1 : zeroMatrix) {
for (int j = 0; j < inputMatrix1.length; j++) {
System.out.print(inputMatrix1[j] + " ");
}
System.out.println();
}
System.out.println();
// 1.9
System.out.println("===== 1.9 =====");
inputString1 = "waterbottle";
inputString2 = "erbottlewat";
output = StringAlgorithms.stringRotation(inputString1, inputString2);
System.out.println("s1: " + inputString1);
System.out.println("s2: " + inputString2);
System.out.println("Is a rotation: " + output);
System.out.println();
// 2.1
System.out.println("===== 2.1 =====");
LinkedList inputLinkedList = new LinkedList();
inputLinkedList.add(1);
inputLinkedList.add(12);
inputLinkedList.add(123);
inputLinkedList.add(12);
inputLinkedList.add(12);
inputLinkedList.add(11);
inputLinkedList.add(1);
inputLinkedList.add(1234);
inputLinkedList.add(14);
inputLinkedList.add(123);
LinkedListAlgorithms.removeDups(inputLinkedList);
ListIterator iterator = inputLinkedList.listIterator();
while (iterator.hasNext()) {
System.out.print(iterator.next() + ", ");
}
System.out.println();
inputLinkedList = new LinkedList();
inputLinkedList.add(1);
inputLinkedList.add(12);
inputLinkedList.add(123);
inputLinkedList.add(12);
inputLinkedList.add(12);
inputLinkedList.add(11);
inputLinkedList.add(1);
inputLinkedList.add(1234);
inputLinkedList.add(14);
inputLinkedList.add(123);
LinkedListAlgorithms.removeDupsNoBuffer(inputLinkedList);
iterator = inputLinkedList.listIterator();
while (iterator.hasNext()) {
System.out.print(iterator.next() + ", ");
}
System.out.println();
System.out.println();
// 2.2
System.out.println("===== 2.2 =====");
SinglyLinkedList inLink = new SinglyLinkedList();
inLink.add(1);
inLink.add(12);
inLink.add(123);
inLink.add(12);
inLink.add(12);
inLink.add(11);
inLink.add(1);
inLink.add(1234);
inLink.add(14);
inLink.add(123);
SinglyLinkedList.Node outNode = LinkedListAlgorithms.kToLast(inLink, 4);
System.out.println(outNode.getData());
System.out.println();
// 2.3
System.out.println("===== 2.3 =====");
System.out.println(inLink.toString());
System.out.println("Deleting node " + outNode.toString() + "...");
LinkedListAlgorithms.deleteMiddleNode(inLink, outNode);
System.out.println(inLink.toString());
System.out.println();
// 2.4
System.out.println("===== 2.4 =====");
System.out.println(inLink.toString());
int partVal = 13;
System.out.println("Partitioning list about " + partVal + "...");
LinkedListAlgorithms.partition(inLink, partVal);
System.out.println(inLink.toString());
System.out.println();
// 2.5
SinglyLinkedList aLinkedNumber = new SinglyLinkedList();
aLinkedNumber.add(7);
aLinkedNumber.add(1);
aLinkedNumber.add(6);
SinglyLinkedList bLinkedNumber = new SinglyLinkedList();
bLinkedNumber.add(5);
bLinkedNumber.add(9);
bLinkedNumber.add(2);
bLinkedNumber.add(1);
SinglyLinkedList linkSum = LinkedListAlgorithms.sumLists(aLinkedNumber, bLinkedNumber);
System.out.println(" " + aLinkedNumber.toString());
System.out.println("+ " + bLinkedNumber.toString());
System.out.println(" ==============");
System.out.println(" " + linkSum.toString());
System.out.println();
// 2.6
System.out.println("===== 2.6 =====");
SinglyLinkedList palindromeLink = new SinglyLinkedList();
palindromeLink.add(5);
palindromeLink.add(7);
palindromeLink.add(8);
palindromeLink.add(9);
palindromeLink.add(8);
palindromeLink.add(7);
palindromeLink.add(5);
output = LinkedListAlgorithms.palindrome(linkSum);
System.out.println("Input: " + linkSum.toString());
System.out.println("Palindrome: " + output);
output = LinkedListAlgorithms.palindrome(palindromeLink);
System.out.println("Input: " + palindromeLink.toString());
System.out.println("Palindrome: " + output);
System.out.println();
// 2.7
System.out.println("===== 2.7 =====");
SinglyLinkedList.Node palindromeFirst = palindromeLink.first();
SinglyLinkedList palindromeCopy = new SinglyLinkedList(palindromeFirst);
palindromeLink.addFront(22);
palindromeLink.addFront(53);
palindromeCopy.addFront(23);
SinglyLinkedList.Node outputNode =
LinkedListAlgorithms.intersection(palindromeLink, palindromeCopy);
System.out.println("Input: " + palindromeLink.toString());
System.out.println("Input: " + palindromeCopy.toString());
if (outputNode == null) {
System.out.println("Output: false");
} else {
System.out.println("Output: " + outputNode.toString());
}
outputNode = LinkedListAlgorithms.intersection(palindromeLink, linkSum);
System.out.println("Input: " + palindromeLink.toString());
System.out.println("Input: " + linkSum.toString());
if (outputNode == null) {
System.out.println("Output: false");
} else {
System.out.println("Output: " + outputNode.toString());
}
System.out.println();
// 2.8
System.out.println("===== 2.8 =====");
SinglyLinkedList circularLinked = new SinglyLinkedList();
circularLinked.add(2);
circularLinked.add(4);
circularLinked.add(6);
circularLinked.add(8);
circularLinked.add(10);
circularLinked.add(12);
circularLinked.add(14);
SinglyLinkedList.Node current = circularLinked.first();
current = current.getNext();
current = current.getNext();
SinglyLinkedList.Node last = circularLinked.last();
last.setNext(current);
outputNode = LinkedListAlgorithms.loopDetection(circularLinked);
System.out.println("Circular Node: " + outputNode.toString());
System.out.println();
// 3.2
StackMin minStack = new StackMin(100);
minStack.push(11);
minStack.push(16);
minStack.push(9);
minStack.push(99);
minStack.push(42);
minStack.push(3);
minStack.push(22);
int outVal = minStack.peek();
System.out.println("Peeking... " + outVal);
outVal = minStack.pop();
System.out.println("Popping... " + outVal);
outVal = minStack.min();
System.out.println("Minimum: " + outVal);
outVal = minStack.pop();
System.out.println("Popping... " + outVal);
outVal = minStack.min();
System.out.println("Minimum: " + outVal);
outVal = minStack.pop();
System.out.println("Popping... " + outVal);
outVal = minStack.min();
System.out.println("Minimum: " + outVal);
outVal = minStack.pop();
System.out.println("Popping... " + outVal);
outVal = minStack.min();
System.out.println("Minimum: " + outVal);
outVal = minStack.pop();
System.out.println("Popping... " + outVal);
outVal = minStack.min();
System.out.println("Minimum: " + outVal);
outVal = minStack.pop();
System.out.println("Popping... " + outVal);
outVal = minStack.min();
System.out.println("Minimum: " + outVal);
outVal = minStack.pop();
System.out.println();
// 3.3
// 5 Stacks each of capacity 5
System.out.println("===== 3.3 =====");
SetOfStacks stackSet = new SetOfStacks(5, 5);
stackSet.push(17);
stackSet.push(16);
stackSet.push(15);
stackSet.push(14);
stackSet.push(13);
stackSet.push(12);
stackSet.push(11);
stackSet.push(10);
stackSet.push(9);
stackSet.push(8);
stackSet.push(7);
stackSet.push(6);
stackSet.push(5);
stackSet.push(4);
stackSet.push(3);
stackSet.push(2);
stackSet.push(1);
System.out.println("Popped: " + stackSet.popAt(1));
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println("Popped: " + stackSet.pop());
System.out.println();
System.out.println("===== 3.4 =====");
MyQueue queue = new MyQueue(100);
queue.push(1);
queue.push(2);
queue.push(3);
System.out.println("Popped: " + queue.pop());
System.out.println("Popped: " + queue.pop());
System.out.println("Popped: " + queue.pop());
System.out.println();
System.out.println("===== 3.5 =====");
Stack sortableStack = new Stack(100);
sortableStack.push(12);
sortableStack.push(21);
sortableStack.push(4);
sortableStack.push(16);
sortableStack.push(17);
sortableStack.push(8);
sortableStack.push(10);
sortableStack.push(15);
sortableStack.push(54);
sortableStack.push(12);
StackAlgorithms.sortStack(sortableStack);
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println("Popped: " + sortableStack.pop());
System.out.println();
System.out.println("===== 3.6 =====");
AnimalShelterQueue animalShelter = new AnimalShelterQueue();
animalShelter.enqueue(new Dog());
animalShelter.enqueue(new Cat());
animalShelter.enqueue(new Dog());
animalShelter.enqueue(new Cat());
animalShelter.enqueue(new Dog());
animalShelter.enqueue(new Cat());
animalShelter.enqueue(new Dog());
animalShelter.enqueue(new Cat());
animalShelter.enqueue(new Dog());
animalShelter.enqueue(new Cat());
animalShelter.enqueue(new Dog());
animalShelter.enqueue(new Cat());
animalShelter.enqueue(new Dog());
animalShelter.enqueue(new Cat());
System.out.println(animalShelter.dequeueAny());
System.out.println(animalShelter.dequeueAny());
System.out.println(animalShelter.dequeueAny());
System.out.println(animalShelter.dequeueAny());
System.out.println(animalShelter.dequeueCat());
System.out.println(animalShelter.dequeueCat());
System.out.println(animalShelter.dequeueCat());
System.out.println();
System.out.println("===== 4.1 =====");
DirectedGraph diGraph = new DirectedGraph();
DirectedGraph.Node node1 = new DirectedGraph.Node(1);
DirectedGraph.Node node2 = new DirectedGraph.Node(2);
DirectedGraph.Node node3 = new DirectedGraph.Node(3);
DirectedGraph.Node node4 = new DirectedGraph.Node(4);
DirectedGraph.Node node5 = new DirectedGraph.Node(5);
DirectedGraph.Node node6 = new DirectedGraph.Node(6);
DirectedGraph.Node node7 = new DirectedGraph.Node(7);
DirectedGraph.Node node8 = new DirectedGraph.Node(8);
DirectedGraph.Node node9 = new DirectedGraph.Node(9);
DirectedGraph.Node node10 = new DirectedGraph.Node(10);
DirectedGraph.Node node11 = new DirectedGraph.Node(11);
DirectedGraph.Node node12 = new DirectedGraph.Node(12);
DirectedGraph.Node node13 = new DirectedGraph.Node(13);
DirectedGraph.Node node14 = new DirectedGraph.Node(14);
diGraph.addAdjacency(node1, node2);
diGraph.addAdjacency(node2, node3, node4);
diGraph.addAdjacency(node3, node5);
diGraph.addAdjacency(node4, node6);
diGraph.addAdjacency(node6, node7, node8, node9);
diGraph.addAdjacency(node9, node10);
diGraph.addAdjacency(node11, node12);
diGraph.addAdjacency(node12, node13);
diGraph.addAdjacency(node13, node14);
diGraph.addAdjacency(node14, node7);
System.out.println("Directed Graph: \n" + diGraph);
output = diGraph.routeBetweenNodesExists(node1, node9);
System.out.println("Route between " + node1 + " and " + node9 + " exists: " + output);
output = diGraph.routeBetweenNodesExists(node11, node6);
System.out.println("Route between " + node11 + " and " + node6 + " exists: " + output);
System.out.println();
System.out.println("===== 4.2 =====");
int[] inputArray = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12};
BinaryTree searchTreeOutput;
searchTreeOutput = TreeAlgorithms.minimalTree(inputArray);
System.out.println(searchTreeOutput);
System.out.println();
System.out.println("===== 4.3 =====");
BinaryTree treeOutput;
treeOutput = TreeAlgorithms.minimalTree(inputArray);
List<LinkedList> outputList = treeOutput.linkedListsByDepth();
System.out.println(outputList);
System.out.println();
System.out.println("===== 4.4 =====");
BinaryTree.Node biNode0 = new BinaryTree.Node(0);
BinaryTree.Node biNode1 = new BinaryTree.Node(1);
BinaryTree.Node biNode2 = new BinaryTree.Node(2);
BinaryTree.Node biNode3 = new BinaryTree.Node(3);
BinaryTree.Node biNode4 = new BinaryTree.Node(4);
BinaryTree.Node biNode5 = new BinaryTree.Node(5);
BinaryTree.Node biNode6 = new BinaryTree.Node(6);
BinaryTree.Node biNode7 = new BinaryTree.Node(7);
BinaryTree.Node biNode8 = new BinaryTree.Node(8);
BinaryTree.Node biNode9 = new BinaryTree.Node(9);
BinaryTree.Node biNode10 = new BinaryTree.Node(10);
BinaryTree.Node biNode11 = new BinaryTree.Node(11);
biNode7.addLeftChild(biNode3);
biNode3.addLeftChild(biNode1);
biNode1.addLeftChild(biNode0);
biNode1.addRightChild(biNode2);
biNode3.addRightChild(biNode5);
biNode5.addLeftChild(biNode4);
biNode5.addRightChild(biNode6);
biNode7.addRightChild(biNode10);
biNode10.addLeftChild(biNode8);
biNode8.addLeftChild(biNode9);
output = treeOutput.isBalanced();
System.out.println(" (7) ");
System.out.println(" (3) (11) ");
System.out.println(" (1) (5) (9) (12)");
System.out.println("(0) (2) (4) (6) (8) (10) ");
System.out.println("Is balanced: " + output);
System.out.println();
BinaryTree unbalancedTree = new BinaryTree(biNode7);
output = unbalancedTree.isBalanced();
System.out.println(" (7) ");
System.out.println(" (3) (10) ");
System.out.println(" (1) (5) (8) ");
System.out.println("(0) (2) (4) (6) (9) ");
System.out.println("Is balanced: " + output);
System.out.println();
System.out.println("===== 4.5 =====");
output = treeOutput.isBinarySearchTree();
System.out.println(" (7) ");
System.out.println(" (3) (11) ");
System.out.println(" (1) (5) (9) (12)");
System.out.println("(0) (2) (4) (6) (8) (10) ");
System.out.println("Is BST: " + output);
System.out.println();
output = unbalancedTree.isBinarySearchTree();
System.out.println(" (7) ");
System.out.println(" (3) (10) ");
System.out.println(" (1) (5) (8) ");
System.out.println("(0) (2) (4) (6) (9) ");
System.out.println("Is BST: " + output);
System.out.println();
System.out.println("===== 4.6 =====");
BinarySearchTree.Node bstNode0 = new BinarySearchTree.Node(0);
BinarySearchTree.Node bstNode1 = new BinarySearchTree.Node(1);
BinarySearchTree.Node bstNode2 = new BinarySearchTree.Node(2);
BinarySearchTree.Node bstNode3 = new BinarySearchTree.Node(3);
BinarySearchTree.Node bstNode4 = new BinarySearchTree.Node(4);
BinarySearchTree.Node bstNode5 = new BinarySearchTree.Node(5);
BinarySearchTree.Node bstNode6 = new BinarySearchTree.Node(6);
BinarySearchTree.Node bstNode7 = new BinarySearchTree.Node(7);
BinarySearchTree.Node bstNode8 = new BinarySearchTree.Node(8);
BinarySearchTree.Node bstNode9 = new BinarySearchTree.Node(9);
BinarySearchTree.Node bstNode10 = new BinarySearchTree.Node(10);
BinarySearchTree.Node bstNode11 = new BinarySearchTree.Node(11);
bstNode1.addLeftChild(bstNode0);
bstNode1.addRightChild(bstNode2);
bstNode3.addLeftChild(bstNode1);
bstNode3.addRightChild(bstNode5);
bstNode5.addLeftChild(bstNode4);
bstNode5.addRightChild(bstNode6);
bstNode7.addLeftChild(bstNode3);
bstNode7.addRightChild(bstNode11);
bstNode11.addLeftChild(bstNode9);
bstNode9.addLeftChild(bstNode8);
bstNode9.addRightChild(bstNode10);
System.out.println(bstNode0);
System.out.println(bstNode0.getNext());
System.out.println(bstNode1.getNext());
System.out.println(bstNode2.getNext());
System.out.println(bstNode3.getNext());
System.out.println(bstNode4.getNext());
System.out.println(bstNode5.getNext());
System.out.println(bstNode6.getNext());
System.out.println(bstNode7.getNext());
System.out.println(bstNode8.getNext());
System.out.println(bstNode9.getNext());
System.out.println(bstNode10.getNext());
System.out.println();
System.out.println("===== 4.7 =====");
// 4.7 Build Order: You are given a list of projects and a list of
// dependencies (which is a list of pairs of projects where the first
// project is dependent on the second project). All of a project's
// dependencies must be built before the project is. Find a build order
// that will allow the projects to be built. If there is no valid build
// order, return an error.
// EXAMPLE:
// Input:
// projects: a, b, c, d, e, f
// dependencies: (d, a), (b, f), (d, b), (a, f), (c, d)
// Output: f, e, a, b, d, c
List<Character> listOfProjects = new ArrayList<>();
Character[] projectArray = {'a', 'b', 'c', 'd', 'e', 'f'};
listOfProjects.addAll(Arrays.asList(projectArray));
List<Tuple<Character>> listOfDependencies = new ArrayList<>();
listOfDependencies.add(new Tuple('d', 'a'));
listOfDependencies.add(new Tuple('b', 'f'));
listOfDependencies.add(new Tuple('d', 'b'));
listOfDependencies.add(new Tuple('a', 'f'));
listOfDependencies.add(new Tuple('c', 'd'));
}