Pointer Arithmetic

[Bray101]

My code is working correctly using array notation, but I'm not allowed to use it in this program. I have to use pointer arithmetic. I have an array called yearEndRank [20][6] that we input 5 scores to. The displaying output has to sort them and give the highest ran, which is technically the lowest number. The code I pasted below works, but I am not allowed to use it, since it is not pointer arithmetic. Any help?

  Put the code youint computeHighestRank (int locYearEndRank, int locSlot)
{

  int temp = locYearEndRank[locSlot][1];

    for (int rank = 1; rank < 6; rank++)
    {
      if (locYearEndRank [locSlot][rank] < temp) temp = locYearEndRank [locSlot][rank];
    }

      return temp; need help with here.

[Catfish666]

Let's start with the basics:

int a[20]; // one-dimensional array

a[0] == *(a + 0);
a[1] == *(a + 1);
a[18] == *(a + 18);

So far so good. It gets a little bit trickier with multiple dimensions.

int a[20][10]; // two dimensional array (some would call it matrix)

a[5][8] == /* ??? */;

Well if a[20][10] is a matrix, we can think of 20 as the height, and 10 as the width.

So a[5][8] means we're on line 6, column 9.

(This is because in C++ counting starts from 0 not 1, but we count our lines and columns starting from 1 because we're human.)

Long story short, here's the formula:
a[x][y] == *(a + width_of_a*x + y);

a[5][8] == *(a + 10*5 + 8);

And here's an article your professor should read.
http://www.cplusplus.com/forum/articles/17108/

[Duthomhas]

                                        EQUIVALENT EXPRESSIONS

1 2 3 4 5 6

int a[ 100 ]; a[ 12 ] = 7; for (int i = 0; i < 10; i++) a[ i ] += 1;

int a[ 100 ]; *(a + 12) = 7; for (int* p = a; p < a + 10; p++) *p += 1;

More reading about pointers:

http://www.cplusplus.com/faq/sequences/strings/c-strings-and-pointers/#pointers

view-source:http://www.cplusplus.com/doc/tutorial/pointers/
(Scroll down to "Pointers and Arrays")

Hope this helps.

[Bray101]

Sorry for being basic here, but do I start my pointer when im declaring that function prototype at the beginning of my code? Or does it wait until I'm inside of the main?

[Catfish666]

Sorry for being basic here, but do I start my pointer when im declaring that function prototype at the beginning of my code? Or does it wait until I'm inside of the main?

I don't understand your question.

Perhaps you should read about functions and their parameters:
http://www.cplusplus.com/doc/tutorial/functions/

[Bray101]

Forget that last post, as I have it declared now and running in a for loop.

I still just don't understand how to get the pointer to keep increasing and reading in from my array.

[Duthomhas]

int xs[] = { 7, 8, 9 };  // array of integers 

int* p = &x[ 0 ];  // *p is 7

cout << *p << end;  // prints "7"

p += 1;  // update to point to the next integer

cout << *p << endl; // prints "8" 

Hope this helps.