using pointers insde functions

in the code below i am trying to make a function that will sort an array into numerical order but the syntax i am using below is
wrong. Can anybody tell me what I am doing wrong here .
Thanks!

Code:

---

#include<iostream>
using namespace std;

void SortArray(int* array);

int main(void)
{
        int ages[2]={6,5};
        cout << ages[0] << " " << ages[1] << endl;

        SortArray(ages);

        cout << ages[0] << " " << ages[1] << endl;


        return(0);
}

void SortArray(int* array)
{
        int temp=0;
        int* pnum1=array[0];
        int* pnum2=array[1];

        if(*pnum1>*pnum2)
        {
                temp=*pnum1;
                *pnum1=*pnum2;
                *pnum2=temp;
}

---

I assume the missing } is a typo :)

Try this:

Code:

---

void SortArray(int* array)
{
        int temp=0;
        int* pnum1=&array[0];
        int* pnum2=&array[1];

        if(*pnum1>*pnum2)
        {
                temp=*pnum1;
                *pnum1=*pnum2;
                *pnum2=temp;
        }
}

---

Forget people . This dozy sod(thats me) forgot to use the address of operator!

Endo you just beat me . Congrats on your 100 posts:)

Woohoo, I didn't even notice.

Y'know what you are doing is the beginnings of a bubblesort, that would be much better to use if you're able.

hey, writing a bubble sort method is a great way to familiarize yourself with arrays, and is a good "gateway algorithm" into the more advanced types of sort

Hey Endo youve grown from a boy to a man now:)

Bubble sort ? Is that when you have an array of numbers and you loop while sorting until you get the array in numerical order? If not please give a breif description.

Code:

---

void BubbleSort(int * List, int ListLength)
{
    int SwapNumber, NumberCounter, PassCounter = 0;
    bool SwapMade;
   
    do
    {
        SwapMade = false;
        PassCounter++;
       
        for (NumberCounter = 0; NumberCounter < (ListLength - PassCounter); NumberCounter++)
        {
            if (List[NumberCounter] > List[NumberCounter + 1])
            {
                SwapNumber = List[NumberCounter];
                List[NumberCounter] = List[NumberCounter + 1];
                List[NumberCounter + 1] = SwapNumber;
                SwapMade = true;
            }
        }
    } while (SwapMade);
}

---

Bubble sort moves through the list comparing number [n] to number [n+1]. If [n] is greater than [n+1], the two numbers are swapped. The result is that following each pass through the list, the largest number will 'rise' to the 'top' of the list (Cheesy analogy: like a bubble will rise to the top in a glass of water). Above, the bubble sort moves through the List comparing List[NumberCounter] to List[NumberCounter + 1] and swapping as required. When a swap occurs, the boolean SwapMade is set to true. When no swaps are required (SwapMade == false), the list is sorted and the function exits.

If you're going to write your own sort, you should try a selection sort (just as easy, twice as fast) or, even better, use qsort.

fletch

http://www.aihorizon.com/essays/basi...ting/index.htm

Going back years in my memory:

Code:

---

int i, ii;
int iArray[5] = { 2, 4, 5, 1, 3};

for ( i = 0; i < 5; i++)
{
  for (ii = i + 1; ii < 5; ii ++)
  {
    if ( iArray[i] < iArray[ii])
    {
        int swap = iArray[i];
        iArray[i] = iArray[ii];
        iArray[ii] = swap;
      }
    }
}

---

Untested, but if memory serves than it is correct.

However if you are using C++ than do something like this:

Code:

---

#include <algorithm>

vector<int> iVec;

int x;
while (cin, x)
    iVec.push_back(x);

sort ( iVec.begin(), iVec.end() );

---

Something to this effect works well in C++, however MSVC++ 6 does not support the C++ STL and therefore you can't use this on that particular compiler.