C++ Tutorial/template/generic array

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A generic safe array example

#include <iostream>
#include <cstdlib>
using namespace std;
const int SIZE = 10;
template <class T> class MyType {
  T a[SIZE];
public:
  MyType() {
    register int i;
    for(i=0; i<SIZE; i++) a[i] = i;
  }
  T &operator[](int i){
      if(i<0 || i> SIZE-1) {
        cout << "\nIndex value of ";
        cout << i << " is out-of-bounds.\n";
        exit(1);
      }
      return a[i];
  }
};
int main()
{
  MyType<int> intob;
  MyType<double> doubleob;
  cout << "Integer array: ";
  for(int i=0; i<SIZE; i++)
     intob[i] = i;
  for(int i=0; i<SIZE; i++)
     cout << intob[i] << "  ";
  cout << "\n";
  cout << "Double array: ";
  for(int i=0; i<SIZE; i++)
     doubleob[i] = (double) i/3;
  for(int i=0; i<SIZE; i++)
     cout << doubleob[i] << "  ";
  cout << "\n";
  intob[12] = 100;
  return 0;
}
Integer array: 0  1  2  3  4  5  6  7  8  9
Double array: 0  0.333333  0.666667  1  1.33333  1.66667  2  2.33333  2.66667  3
Index value of 12 is out-of-bounds.

Define your own generic array

#include<iostream.h>
#include<iomanip.h>
template<class T>
class Array
{
  T *elems;
  int size;
  public:
    Array(int s)
    {
      size=s;
      elems=new T[size];
      for(int i=0;i<size;i++)
         elems[i]=0;
    }
    ~Array()
    {
      delete elems;
    }
    T& operator[](int index)
    {
      return elems[index];
    }
    void operator=(T temp)
    {
       for(int i=0;i<size;i++)
               elems[i]=temp;
    }
};
int main()
{
  int n=10;
  Array<int>arr1(n);
  Array<char>arr2(n);
  for(int i=0;i<n;i++)
  {
    arr1[i]="a"+i;
       arr2[i]="a"+i;
  }
  cout <<endl;
  for(int i=0;i<n;i++){
         cout<<setw(8)<<arr1[i]<<setw(8)<<arr2[i]<<endl;
  }
}
97       a
      98       b
      99       c
     100       d
     101       e
     102       f
     103       g
     104       h
     105       i
     106       j