You can use it to makes a backup, a spare copy of your files, or to transport data between computers

tracks

a floppy disk

a portable hard drive

cd-roms

dvds

​

Int main()
{
  int
    *array_X,
    *array_Y,
    numOfEl,
    border_C,
    prevNum;

  cout << "Input N: ";
  cin >> numOfEl;

  array_X = new int[numOfEl];
  array_Y = new int[numOfEl / 2];
  cout << "Input C: ";
  cin >> border_C;

  for (int i = 0; i < numOfEl; i++)
    cin >> array_X[i];

  prevNum = border_C;
  for (int i = 0, j = 0; i < numOfEl; i += 2)
    if (array_X[i] < border_C && array_X[i] != prevNum)
      array_Y[j++] = prevNum = array_X[i];

  cout << endl;
  for (int i = 0; i < numOfEl; i++)
    cout << array_X[i] << "; ";

  cout << endl;
  for (int i = 0; i < numOfEl / 2; i++)
    cout << array_Y[i] << "; ";

  system("pause");

  return 0;
} /* End of the 'main' function */

#include <iostream>
#include <cmath>

using namespace std;

int main()
{
  int
    numOfSides,
    diameter;
  double
    polygonArea;

  cout << "Input number of sides: ";
  cin >> numOfSides;
  cout << "Input the diameter of the inscribed circle: ";
  cin >> diameter;

  polygonArea = numOfSides * (diameter * diameter / 4) * tan(PI / numOfSides);

  cout << "Polygon area = " << polygonArea << ";\nDelta = "
      << 1 - (PI * (diameter * diameter / 4)) / polygonArea << endl;

  system("pause");

  return 0;
} /* End of the 'main' function */