diff --git a/LinearList/arrayList.cpp b/LinearList/arrayList.cpp
new file mode 100644
index 0000000..dc0ec46
--- /dev/null
+++ b/LinearList/arrayList.cpp
@@ -0,0 +1,133 @@
+#include <iostream>
+#include <string>
+#include "linearList.h"
+#include "arrayList.h"
+
+template <typename T>
+int search(const T& x, const T* arr, int n, int length) {
+	if (n >= length)
+		return -1;
+	if (arr[n] == x)
+		return n;
+	return search(x, arr, n + 1 , length);
+}
+
+template <typename T>
+arrayList<T>::arrayList(int initialCapacity) {
+	if (initialCapacity < 1) {
+		std::cout << "Initial Capacity Must Be > 0" << std::endl;
+		//¿¼ÂÇthrow exception
+	}
+	element = new T[initialCapacity];
+	listSize = 0;
+}
+
+template <typename T>
+arrayList<T>::arrayList(const arrayList<T>& theList) {
+	//É±´
+	arrayLength = theList.arrayLength;
+	listSize = theList.listSize;
+	element = new T[arrayLength];
+	for (int i = 0; i < listSize; i++) {
+		element[i] = theList.element[i];
+	}
+}
+
+template <typename T>
+arrayList<T>::~arrayList() {
+	delete [] element;
+}
+
+template <typename T>
+int arrayList<T>::capacity() {
+	return arrayLength;
+}
+
+template <typename T>
+bool arrayList<T>::empty() const {
+	//If empty, return true;
+	if (listSize == 0) return true;
+	return false;
+} 
+
+template <typename T>
+int arrayList<T>::size() const {
+	//Return Array Size
+	return listSize;
+}
+
+template <typename T>
+T& arrayList<T>::get(int theIndex) const {
+	// Return Arr[theIndex]
+	if (theIndex < 0 || theIndex >= listSize) {
+		throw std::out_of_range("Index out of bounds: " + std::to_string(theIndex));
+	}
+	return element[theIndex];
+} 
+
+template <typename T>
+int arrayList<T>::indexOf(const T& theElement) const {
+	//Return the index of "theElement" first appeared
+	return search(theElement, element, 0, listSize);
+} 
+
+template <typename T>
+T* arrayList<T>::changeLength(T* x, int oldlength, int newlength) {
+	//Arr length altered
+	if (newlength < 0) {
+		throw std::invalid_argument("newlength must be non-negative: " + std::to_string(newlength));
+	}
+	T* tmp = new T[newlength];
+	int min = std::min(newlength, oldlength);
+	for (int i = 0; i < min; i++) {
+		tmp[i] = x[i];
+	}
+	delete[] x;
+	return tmp;
+}
+
+
+template <typename T>
+void arrayList<T>::erase(int theIndex) {
+	//Erase Arr[theIndex] , remember to move the rest
+	if (theIndex < 0 || theIndex >= listSize) {
+		throw std::out_of_range("Index out of bounds: " + std::to_string(theIndex));
+	}
+	for (int i = theIndex; i < listSize - 1; i++) {
+		element[i] = element[i + 1];
+	}
+	listSize--;
+	element[listSize] = T();
+} 
+
+template <typename T>
+void arrayList<T>::insert(int theIndex, const T& theElement) {
+	//Insert theElement to place Arr[theIndex]
+	if (theIndex < 0 || theIndex > listSize) {
+		throw std::out_of_range("Index out of bounds: " + std::to_string(theIndex));
+	}
+	if (listSize == arrayLength) {
+		element = changeLength(element, arrayLength, arrayLength + 1);
+		
+		arrayLength++;
+	}
+	for (int i = listSize - 1; i >= theIndex; --i) {
+		element[i + 1] = element[i];
+	}
+	element[theIndex] = theElement;
+	listSize++;
+}
+
+template <typename T>
+void arrayList<T>::output() const {
+	// output into ostream
+	for (int i = 0; i < listSize; i++) {
+		std::cout << element[i] << " ";
+	}
+	std::cout << std::endl;
+}
+
+template class arrayList<int>;
+template class arrayList<double>;
+template class arrayList<char>;
+
diff --git a/LinearList/arrayList.h b/LinearList/arrayList.h
new file mode 100644
index 0000000..630a5c0
--- /dev/null
+++ b/LinearList/arrayList.h
@@ -0,0 +1,28 @@
+#ifndef ARRAY_LIST
+#define ARRAY_LIST
+
+#include <iostream>
+#include "linearList.h"
+
+template <typename T>
+class arrayList : public linearList<T> {
+public:
+	arrayList(int initialCapacity = 10);
+	arrayList(const arrayList<T>& x);
+	~arrayList();
+	int capacity();
+	bool empty() const;//If empty, return 0;
+	int size() const; //Return Array Size
+	virtual T& get(int theIndex) const override; // Return Arr[theIndex]
+	virtual int indexOf(const T& theElement) const override; //Return the index of "theElement" first appeared
+	virtual void erase(int theIndex) override; //Erase Arr[theIndex] 
+	virtual T* changeLength(T* x, int oldlength, int newlength) override;
+	virtual void insert(int theIndex, const T& theElement) override; //Insert theElement to place Arr[theIndex]
+	virtual void output() const override; //cout
+private:
+	T* element;
+	int arrayLength;
+	int listSize;
+};
+#endif
+
diff --git a/LinearList/linearList.h b/LinearList/linearList.h
new file mode 100644
index 0000000..bb4c726
--- /dev/null
+++ b/LinearList/linearList.h
@@ -0,0 +1,20 @@
+#ifndef LINEAR_LIST
+#define LINEAR_LIST
+#include <iostream>
+
+template <typename T>
+class linearList {
+public:
+	virtual ~linearList() {};
+	virtual bool empty() const = 0; //If empty, return 0;
+	virtual int size() const = 0; //Return Array Size
+	virtual T& get(int theIndex) const = 0; // Return Arr[theIndex]
+	virtual int indexOf(const T& theElement) const = 0; //Return the index of "theElement" first appeared
+	virtual void erase(int theIndex) = 0; //Erase Arr[theIndex] 
+	virtual T* changeLength(T* x, int oldlength, int newlength) = 0;
+	virtual void insert(int theIndex, const T& theElement) = 0; //Insert theElement to place Arr[theIndex]
+	virtual void output() const = 0; //cout		
+};
+
+
+#endif
\ No newline at end of file
diff --git a/LinearList/main.cpp b/LinearList/main.cpp
new file mode 100644
index 0000000..6976fac
--- /dev/null
+++ b/LinearList/main.cpp
@@ -0,0 +1,49 @@
+#include <iostream>
+#include "linearList.h"
+#include "arrayList.h"
+/*
+	NEEDED TEST:
+ok	int capacity();
+ok	bool empty() const;//If empty, return 0;
+ok	int size() const; //Return Array Size
+ok	virtual T& get(int theIndex) const override; // Return Arr[theIndex]
+	virtual int indexOf(const T & theElement) const override; //Return the index of "theElement" first appeared
+ok	virtual void erase(int theIndex) override; //Erase Arr[theIndex]
+ok	virtual T* changeLength(T * x, int oldlength, int newlength) override;
+ok	virtual void insert(int theIndex, const T & theElement) override; //Insert theElement to place Arr[theIndex]
+ok	virtual void output(std::ostream & out) const override; //cout
+*/
+int main() {
+	arrayList<int> test(10);
+	std::cout << "ArrayCapacity: " << test.capacity() << std::endl;
+	std::cout << "Is Empty: " << test.empty() << std::endl;
+	for (int i = 0; i < 10; i++) {
+		test.insert(i, i + 1);
+	}
+	test.output();
+	std::cout << test.get(4) << std::endl ; //output 5
+	test.insert(10, 11); // 1 2 3 4 5 6 7 8 9 10 11
+	test.output();
+	std::cout << test.size() << std::endl;
+	test.erase(0); // 2 3 4 5 6 7 8 9 10 11
+	test.output();
+
+	test.insert(5, 3);
+	test.output();
+	std::cout << test.indexOf(3) << std::endl;
+	return 0;
+}
+
+/*
+Output is down below
+
+ArrayCapacity: 0
+Is Empty: 1
+1 2 3 4 5 6 7 8 9 10
+5
+1 2 3 4 5 6 7 8 9 10 11
+11
+2 3 4 5 6 7 8 9 10 11
+2 3 4 5 6 3 7 8 9 10 11
+1
+*/
\ No newline at end of file