Switch 06 and 01b

7 files changed, 224 insertions, 171 deletions

diff --git a/src/01/06/Makefile b/src/01/06/Makefile
new file mode 100644
index 0000000..8120d17
--- /dev/null
+++ b/src/01/06/Makefile
@@ -0,0 +1,37 @@
+#!/usr/bin/make -f
+SHELL=/bin/sh
+
+CC=clang
+TEST_LIBS = -lcgreen
+
+BUILDDIR := build
+OBJS := $(addprefix $(BUILDDIR)/,min_stack.o)
+TEST_OBJS := $(addprefix $(BUILDDIR)/,min_stack_test.o)
+
+$(BUILDDIR)/%.o : %.c
+	$(COMPILE.c) $(OUTPUT_OPTION) $<
+
+.PHONY: all
+all: $(OBJS) $(BUILDDIR)/main.o
+	$(CC) $(OBJS) $(BUILDDIR)/main.o -o $(BUILDDIR)/program
+
+.PHONY: test
+test: $(OBJS) $(TEST_OBJS)
+	$(CC) $(OBJS) $(TEST_OBJS) $(TEST_LIBS) -o $(BUILDDIR)/test
+
+$(OBJS): | $(BUILDDIR)
+
+$(TEST_OBJS): | $(BUILDDIR)
+
+$(BUILDDIR):
+	mkdir $(BUILDDIR)
+
+.PHONY: clean
+clean:
+	rm -fr build
+
+run : all
+	./build/program
+
+run_test : test
+	cgreen-runner -c -v $(BUILDDIR)/test
diff --git a/src/01/06/README.md b/src/01/06/README.md
index ceab17a..f288e0f 100644
--- a/src/01/06/README.md
+++ b/src/01/06/README.md
@@ -1,13 +1,14 @@
-# Learning Profile for Assignment #1 - Question #1b - Computer Science 272: Data Structures and Algorithms
+# Learning Profile for Assignment #1 - Question #6 - Computer Science 272: Data Structures and Algorithms
 
 Name: Mo Khan
 Student ID: 3431709
 
 1. Problem Statement:
 
-Implement the stack methods `push(x)` and `pop()` using two queues.
+Design and implement a MinStack data structure that can store comparable elements and supports the stack operations `push(x)`, `pop()`, and `size()`,
+as well as the `min()` operation, which returns the minimum value currently stored in the data structure.
 
-Analyze the running time of the push(x) and pop() operations based on this implementation.
+All operations should run in constant time.
 
 2. Description of the Code:
 3. Errors and Warnings:
diff --git a/src/01/06/main.c b/src/01/06/main.c
new file mode 100644
index 0000000..f90e37f
--- /dev/null
+++ b/src/01/06/main.c
@@ -0,0 +1,8 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+int main(int argc, char *argv[])
+{
+  printf("=== COMP-272 - Assignment 1 - Question 1b ===\n");
+  return 0;
+}
diff --git a/src/01/06/min_stack.c b/src/01/06/min_stack.c
new file mode 100644
index 0000000..adb96c8
--- /dev/null
+++ b/src/01/06/min_stack.c
@@ -0,0 +1,72 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include "min_stack.h"
+
+Stack *initialize() {
+  Stack *self = malloc(sizeof(Stack));
+  self->head = NULL;
+  return self;
+}
+
+int size(Stack *self) {
+  Node *current = self->head;
+  int i;
+  for (i = 0; current != NULL; i++)
+    current = current->next;
+  return i;
+}
+
+static Node *new(int data) {
+  Node *node = malloc(sizeof(Node));
+  node->next = NULL;
+  node->data = data;
+  return node;
+}
+
+static int compare(int x, int y) {
+  return x == y ? 0 : (x > y) ? 1 : -1;
+}
+
+static void insert(Node **self, int data) {
+  int comparison = compare(data, (*self)->data);
+  Node *node = new(data);
+
+  switch(comparison) {
+    case 1:
+      if ((*self)->next)
+        insert(&((*self)->next), data);
+      else
+        (*self)->next = node;
+      break;
+    default:
+      node->next = *self;
+      *self = node;
+      break;
+  }
+}
+
+void push(Stack *self, int data) {
+  if (self->head)
+    insert(&self->head, data);
+  else
+    self->head = new(data);
+}
+
+int min(Stack *self) {
+  if (self && self->head)
+    return self->head->data;
+
+  return (int)NULL;
+}
+
+int pop(Stack *self) {
+  if (!self->head)
+    return (int)NULL;
+
+  Node *current = self->head;
+  int data = current->data;
+  self->head = current->next;
+  current->next = NULL;
+  free(current);
+  return data;
+}
diff --git a/src/01/06/min_stack.h b/src/01/06/min_stack.h
new file mode 100644
index 0000000..567b0a4
--- /dev/null
+++ b/src/01/06/min_stack.h
@@ -0,0 +1,16 @@
+struct node {
+  int data;
+  struct node *next;
+};
+
+typedef struct node Node;
+
+typedef struct {
+  Node *head;
+} Stack;
+
+Stack *initialize();
+void push(Stack *self, int data);
+int pop(Stack *self);
+int size(Stack *self);
+int min(Stack *self);
diff --git a/src/01/06/min_stack_test.c b/src/01/06/min_stack_test.c
new file mode 100644
index 0000000..a02c163
--- /dev/null
+++ b/src/01/06/min_stack_test.c
@@ -0,0 +1,87 @@
+#include <cgreen/cgreen.h>
+#include "min_stack.h"
+
+Describe(MinStack);
+BeforeEach(MinStack){ }
+AfterEach(MinStack){ }
+
+Ensure(MinStack, when_empty) {
+  Stack *stack = initialize();
+
+  assert_that(size(stack), is_equal_to(0));
+  assert_that(min(stack), is_equal_to(NULL));
+  assert_that(pop(stack), is_equal_to(NULL));
+
+  free(stack);
+}
+
+Ensure(MinStack, when_pushing_a_single_integer) {
+  Stack *stack = initialize();
+
+  push(stack, 1);
+
+  assert_that(size(stack), is_equal_to(1));
+  assert_that(min(stack), is_equal_to(1));
+  assert_that(pop(stack), is_equal_to(1));
+  assert_that(size(stack), is_equal_to(0));
+
+  free(stack);
+}
+
+Ensure(MinStack, when_pushing_multiple_integers_out_of_order) {
+  Stack *stack = initialize();
+
+  push(stack, 2);
+  push(stack, 3);
+  push(stack, 1);
+
+  assert_that(size(stack), is_equal_to(3));
+  assert_that(min(stack), is_equal_to(1));
+
+  assert_that(pop(stack), is_equal_to(1));
+  assert_that(size(stack), is_equal_to(2));
+
+  assert_that(pop(stack), is_equal_to(2));
+  assert_that(size(stack), is_equal_to(1));
+
+  assert_that(pop(stack), is_equal_to(3));
+  assert_that(size(stack), is_equal_to(0));
+
+  assert_that(pop(stack), is_equal_to(NULL));
+  assert_that(size(stack), is_equal_to(0));
+
+  free(stack);
+}
+
+Ensure(MinStack, when_pushing_duplicate_values_on_to_the_stack) {
+  Stack *stack = initialize();
+
+  push(stack, 2);
+  push(stack, 1);
+  push(stack, 2);
+
+  assert_that(size(stack), is_equal_to(3));
+  assert_that(min(stack), is_equal_to(1));
+
+  assert_that(pop(stack), is_equal_to(1));
+  assert_that(pop(stack), is_equal_to(2));
+  assert_that(pop(stack), is_equal_to(2));
+  assert_that(pop(stack), is_equal_to(NULL));
+
+  free(stack);
+}
+
+TestSuite *min_stack_tests() {
+  TestSuite *suite = create_test_suite();
+
+  add_test_with_context(suite, MinStack, when_empty);
+  add_test_with_context(suite, MinStack, when_pushing_a_single_integer);
+  add_test_with_context(suite, MinStack, when_pushing_multiple_integers_out_of_order);
+  return suite;
+}
+
+int main(int argc, char **argv) {
+  TestSuite *suite = create_test_suite();
+  add_suite(suite, min_stack_tests());
+  return run_test_suite(suite, create_text_reporter());
+}
diff --git a/src/01/06/stack_test.c b/src/01/06/stack_test.c
deleted file mode 100644
index b34c191..0000000
--- a/src/01/06/stack_test.c
+++ /dev/null
@@ -1,168 +0,0 @@
-#include <cgreen/cgreen.h>
-
-/*
-Implement the stack methods using two queues
-
-* `push(x)`
-* `pop()`
-
-Analyze the running time of the `push(x)` and `pop()` operations based on this implementation.
-*/
-
-struct node {
-  int data;
-  struct node *next;
-};
-
-typedef struct node Node;
-
-typedef struct {
-  Node *head;
-  int size;
-} Queue;
-
-typedef struct {
-  Queue *q1;
-} Stack;
-
-static Queue *newQueue(){
-  Queue *queue = malloc(sizeof(Queue));
-  queue->size = 0;
-  queue->head = NULL;
-  return queue;
-}
-
-static Stack *initialize() {
-  Stack *stack = malloc(sizeof(Stack));
-  stack->q1 = newQueue();
-  return stack;
-}
-
-Node *newNode(int data) {
-  Node *node = malloc(sizeof(Node));
-  node->data = data;
-  node->next = NULL;
-  return node;
-}
-
-void enqueue(Queue *q, int data) {
-  Node *node = newNode(data);
-  q->size++;
-
-  if (q->head == NULL) {
-    q->head = node;
-  } else {
-    Node *tail = q->head;
-
-    while (tail->next != NULL)
-      tail = tail->next;
-    tail->next = node;
-  }
-}
-
-int dequeue(Queue *q) {
-  if (q->head == NULL) return -1;
-
-  Node *node = q->head;
-  int data = node->data;
-
-  q->head = node->next;
-  free(node);
-  return data;
-}
-
-// The running time is linear time.
-static void push(Stack *stack, int data) {
-  enqueue(stack->q1, data);
-}
-
-// The running time is linear time.
-static int pop(Stack *stack) {
-  int count = stack->q1->size - 1;
-  Queue *tmp = newQueue();
-
-  for (int i = 0; i < count; i++)
-    enqueue(tmp, dequeue(stack->q1));
-
-  int data = dequeue(stack->q1);
-  free(stack->q1);
-  stack->q1 = tmp;
-  return data;
-}
-
-int size(Stack *stack) {
-  return stack->q1->size;
-}
-
-static void destroy(Stack *stack) {
-  int count = size(stack);
-
-  for (int i = 0; i < count; i++)
-    pop(stack);
-
-  free(stack->q1);
-  free(stack);
-}
-
-static void inspect(Queue *q) {
-  Node *tmp = q->head;
-
-  if (q->size == 0) {
-    printf("[]\n");
-    return;
-  }
-
-  printf("[");
-  for (int i = 0; i < q->size; i++) {
-    printf("%d,", tmp->data);
-    tmp = tmp->next;
-  }
-  printf("\b]\n");
-}
-
-Describe(Stack);
-BeforeEach(Stack){ }
-AfterEach(Stack){ }
-
-Ensure(Stack, push_onto_stack) {
-  Stack *stack = initialize();
-
-  push(stack, 1);
-  assert_that(size(stack), is_equal_to(1));
-
-  push(stack, 2);
-  assert_that(size(stack), is_equal_to(2));
-
-  destroy(stack);
-}
-
-Ensure(Stack, pop_single_item) {
-  Stack *stack = initialize();
-
-  push(stack, 1);
-
-  assert_that(pop(stack), is_equal_to(1));
-  destroy(stack);
-}
-
-Ensure(Stack, pop_successive_items) {
-  Stack *stack = initialize();
-
-  push(stack, 1);
-  push(stack, 2);
-
-  assert_that(pop(stack), is_equal_to(2));
-  assert_that(pop(stack), is_equal_to(1));
-
-  destroy(stack);
-}
-
-TestSuite *stack_tests() {
-  TestSuite *suite = create_test_suite();
-
-  add_test_with_context(suite, Stack, push_onto_stack);
-  add_test_with_context(suite, Stack, pop_single_item);
-  add_test_with_context(suite, Stack, pop_successive_items);
-
-  return suite;
-}