how do I reverse order of my array

How do I reverse the order of this array?

Jose

Code:

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#include <iostream.h>
#include <stdlib.h>

const int myarraysize = 5;

void Fill_array(double myarray[], int j);
void Show_array(double myarray[], int j);
void Reverse_array(double myarray[], int j);

int main()
{
    cout << "starting in main" << endl;

    double uservalues[myarraysize] = {};

      Fill_array(uservalues, myarraysize);
      Show_array(uservalues, myarraysize);
      Reverse_array(uservalues, myarraysize);
      Show_array(uservalues, myarraysize);

      cout << "back in main" << endl;

      system("PAUSE");
      return 0;
}

void Fill_array(double myarray[], int j)
{
    cout << "I'm in Fill array" << endl;
    int numberofentries = 0;
    int counter = 0;

    for (int i = 0; i < j; i++)
        {
        cout << "Enter a value to be stored in array" << endl;
        cin >>  myarray[i];
        counter = counter + 1;
        }

    numberofentries = counter;
    cout << "Values you entered: " << numberofentries << endl;

}

void Show_array(double myarray[], int j)
{

    cout << "Now I'm in Show array" << endl;
    cout << "This is what you entered into the array" << endl;
    for (int i = 0; i < j; i++)
        {
        cout << myarray[i] << endl;
        }

}

void Reverse_array(double myarray[], int j)
{
    cout << "Now I'm in Reverse array" << endl;
    myarray[0] = myarray[4];
    myarray[1] = myarray[3];
    myarray[2] = myarray[2];
    //myarray[3] = myarray[4];
    //myarray[4] = myarray[3];

}

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Traverse the array from the beginning until you reach the middle. Swap the first element with the last, second element with the second last etc...

Code:

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void SwapValues(double* Value1, double* value2)
{
  double Temp = *Value1;
  *Value1 = *Value2;
  *Value2 = Temp;
}

void ReverseArray(double MyArray[], int SizeOfArray)
{
  for(int i = 0; i < (int)(SizeOfArray / 2); i++)
  {
      SwapValues(&MyArray[i], &MyArray[SizeOfArray - i - 1]);
  }
}

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use a temporary variable to swap values:

Code:

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void reverseArray(int * array, int num)
{
  int temp;
  int i;
  int number = num - 1;//assumes num is number of ints in array
  for(i = 0; i < num/2; i++, number--)
  { 
      temp = array[number];
      array[number] = array[i];
      arrary[i] = temp;
    }
}

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Allow me to introduce something wonderful:

S T L !!!

Code:

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#include <algorithm>

void ReverseArray(double* array, int size)
{
 std::reverse(array,array+size);
}

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if you have access to STL, go for it! If you want to know what STL is doing, study the other two posts.

I believe this would work too (incomplete but you can fill in whats needed, which isn't much)-

Code:

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for(y = (j-1); y >= 0; y--)
    {
        temparray[y] = myarray[x];
        x++;
    }
        for(x=0; x < j; x++)
    {
          myarray[x] = temparray[x];
    }

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There, that works. Fairly simple to understand, too, IMHO.

Thanks all that helped, I am newbie to C++ and am taking a college course this semester. This is my final working program.

God bless,
Jose

Code:

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//Jose Gonzales, #c++04, 95

#include <iostream.h>
#include <stdlib.h>
const int myarraysize = 5;
int baddata = 0;

void Fill_array(double myarray[], int j);
void Show_array(double myarray[], int j);
void Reverse_array(double myarray[], double myrevarray[], int j);
void Swap_array(double myarray[], double myrevarray[]);

int main()
{

    double uservalues[myarraysize] = {};
    double uservaluesreverse[myarraysize] = {};


      cout << "\n";
      cout << "Enter " << myarraysize <<" double values to be stored in array" << flush << endl;
      Fill_array(uservalues, myarraysize);
      cout << "\n";

      if (baddata == 0)
      {
      cout << "This is what you entered into the array" << endl;
      Show_array(uservalues, myarraysize);
      cout << "\n";
      Reverse_array(uservalues, uservaluesreverse, myarraysize);
      cout << "Now here are your values in reverse order" << endl;
      Show_array(uservaluesreverse, myarraysize);
      cout << "\n";
      Swap_array(uservalues, uservaluesreverse);
      cout << "your values in reverse order all but 1st and last elements of array" << endl;
      Show_array(uservalues, myarraysize);
      }
      cout << "\n";
      cout << "\n";
      cout << "\n";
      cout << "\n";
      cout << "\n";

      system("PAUSE");
      return 0;
}

void Fill_array(double myarray[], int j)
{
    int numberofentries = 0;
    int counter = 0;

    for (int i = 0; i < j; i++)
        {
            if (!cin)
            {
            cin.clear();
            cout << "bad input, goodbye." << endl;
            cout << "\n";
            baddata = 1;
            break;
            }
            else
            {
            cin >>  myarray[i];
            counter = counter + 1;
            }
        }

    numberofentries = counter;
    cout << "total number of entries: " << numberofentries << endl;
}

void Show_array(double myarray[], int j)
{
    for (int i = 0; i < j; i++)
        {
        cout << myarray[i] << endl;
        }
}

void Reverse_array(double myarray[], double myrevarray[], int j)
{
    for (int i=0; i<j; i++)
        {
            myrevarray[i] = myarray[j - i -1];
        }
}

void Swap_array(double myarray[], double myrevarray[])
{
    myarray[1] = myrevarray[1];
    myarray[2] = myrevarray[2];
    myarray[3] = myrevarray[3];
}

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