implemented linked list in cpp (tested) (#260)

implemented linked list in cpp (tested)

Author: piyush6348

Structures/LinkedList.cpp

@@ -0,0 +1,157 @@
+#include <stdlib.h>
+#include <cassert>
+#include <cstdio>
+
+void append(int element);
+void clear(void);
+int max(void);
+int get(unsigned int position);
+void remove_element(unsigned int position);
+
+struct Node 
+{
+	int value;
+	struct Node* next;
+};
+
+static struct Node* head = 0;
+
+void append(int element)
+{
+	if (!head)
+	{
+		head = (struct Node*)malloc(sizeof(struct Node));
+		head->value = element;
+		head->next = 0;
+	}	
+	else 
+	{
+		struct Node* iterator = head;
+		while (iterator->next != 0)
+			iterator = iterator->next;
+
+		iterator->next = (struct Node*)malloc(sizeof(struct Node));
+		iterator->next->value = element;
+		iterator->next->next = 0;
+	}
+}
+
+void clear(void)
+{
+	if (head == 0)
+		return;
+
+	struct Node* iterator = head;
+	struct Node* iterator2;
+	while (iterator != 0)
+	{
+		iterator2 = iterator->next;
+		free(iterator);
+		iterator = iterator2;
+	}
+	head = 0;
+}
+
+int max(void)
+{
+	int max = 0;
+	for (struct Node* iterator = head; iterator; iterator = iterator->next)
+		if (iterator->value > max)
+			max = iterator->value;
+
+	return max;
+}
+
+
+int get(unsigned int position)
+{
+	struct Node* iterator = head;
+	for (int i = 0; i < position; i++)
+	{
+		if (!iterator || !iterator->next)
+			return 0;
+
+		iterator = iterator->next;
+	}
+
+	return iterator->value;
+}
+
+void remove_element(unsigned int position)
+{
+	struct Node* iterator = head;
+	struct Node* prev_iterator = head;
+	for (int i = 0; i < position; i++)
+	{
+		if (!iterator || !iterator->next)
+			return;
+
+		prev_iterator = iterator;
+		iterator = iterator->next;
+	}
+
+	if(position == 0)
+	{
+		head = iterator->next;
+		free(iterator);
+	}
+	else
+	{
+		iterator = iterator->next;
+		free(prev_iterator->next);
+		prev_iterator->next = iterator;
+	}
+}
+
+/////////
+//TESTS//
+/////////
+
+void max_of_one_element_is_same_element(void)
+{
+	append(5);
+	assert(max() == 5);
+	clear();
+}
+
+void max_of_three_elements(void)
+{
+	append(3);
+	append(5);
+	append(2);
+	assert(max() == 5);
+	clear();
+}
+
+void get_returns_element_in_position(void)
+{
+	append(3);
+	append(5);
+	append(7);
+	assert(get(2) == 7);
+	assert(get(0) == 3);
+	assert(get(500) == 0);
+	clear();
+}
+
+void erasing_elements(void)
+{
+	append(3);
+	append(5);
+	append(7);
+	remove_element(1);
+	assert(get(0) == 3);
+	assert(get(1) == 7);
+	assert(get(2) == 0);
+	clear();
+}
+
+
+int main (void)
+{
+	max_of_one_element_is_same_element();
+	max_of_three_elements();
+	get_returns_element_in_position();
+	erasing_elements();
+	printf("All tests passed!\r\n");
+}