add vector class

VecbyClass.cpp

@@ -0,0 +1,136 @@
+#include<iostream>
+
+using namespace std;
+
+template<typename T>
+class Vector {
+
+private:
+    int size=0;
+    int capacity=1;
+    T* arr;
+public:
+    Vector(int size_array,T* a){
+        size=size_array;
+        capacity=size*2;
+        arr=new T[capacity];
+        for (int i = 0; i < size; ++i) {
+            arr[i] = a[i];
+        }
+    
+    }
+
+    Vector(){
+        arr= new T[capacity];
+    }
+    ~Vector(){
+       delete[]arr;
+
+    }
+    
+
+void push_back(T data){
+    if (size==capacity){
+        T*temp = new T[capacity*2];
+        for (int i=0;i<size;i++){
+            temp[i]=arr[i];
+        }
+        delete[]arr;
+        arr=temp;
+        capacity*=2;
+    }
+    arr[size]=data;
+    // cout<<endl;
+    size++;
+}
+
+void pop_back(){
+    size-=1;
+    T* temp= new T[capacity];
+    for (int i;i<size;i++){
+        temp[i]=arr[i];
+    }
+    delete[]arr;
+    arr=temp;
+}
+
+T &get(int index){
+    // cout<<" a ";
+    return arr[index];
+}
+
+int get_size(){
+    return size;
+}
+
+void resize(int new_size){
+    T default_var;
+    if (new_size<size){
+    T* temp= new T[new_size];
+    for (int i=0;i<new_size;i++){
+        temp[i]=arr[i];
+    }
+    delete[]arr;
+    arr=temp;
+    }
+    else{
+    T* temp= new T[new_size];
+    for (int i=0;i<new_size;i++){
+        temp[i]=arr[i];
+    }
+    delete[]arr;
+    arr=temp;
+    }
+    capacity=2*new_size;
+    size=new_size;
+}
+/// 
+int get_capacity(){
+
+    return capacity;
+}
+
+T& operator[](int a){return arr[a];}
+
+};
+// template<typename T>
+// std::ostream& operator<<(std::ostream& out , Vector<T > b)
+// {
+//      for (int i=0;i<b.get_size();i++){
+//     out << b[i] <<",";
+//     }
+//     return out;
+// }
+
+int main(){
+    int myarray[]={};
+    Vector<int> vec = Vector<int> ();
+    Vector<string> vec1 = Vector<string> ();
+    cout<<endl;
+    vec.push_back(1);
+    vec.push_back(2);
+    vec.push_back(3);
+    vec[2]=4;
+    // vec.push_back(4);
+    // cout<<vec;
+    for (int i=0;i<vec.get_size();i++){
+    cout << vec[i] <<"  ";
+    }
+    // vec.pop_back();
+    // for (int i=0;i<vec.get_size();i++){
+    // cout << vec[i] <<"  ";
+    // }
+    // vec1.push_back("ali");
+    // vec1.push_back("o");
+    // for (int i=0;i<vec1.get_size();i++){
+    // cout << vec1[i] <<"  ";
+    // }
+    // vec1.push_back("p");
+    // vec1.push_back("hello");
+    // // vec1.pop_back();
+    // vec1.resize(8);
+    // for (int i=0;i<vec1.get_size();i++){
+    // cout << vec1[i] <<"  ";
+    // }
+    return 0;
+}