Homework question, My code posted.

ripwheels8 · 07-23-2004, 10:11 PM

This is the question:

Write a C program to reverse the digits of a positive integer number. For example, if the number 8735 is entered, the number displayed should be 5378. (Hint: Use a do statement and continuously strip off and display the units digit of the number. If the variable num initially contains the number entered, the units digit is obtained as (num % 10). After a units digit is displayed, dividing the number by 10 sets up the number for the next iteration. Thus, (8735 % 10) is 5 and (8735 / 10) is 873. The do statement should continue as long as the remaining number is not zero).

This is my code:

void findmax(int val[10][20])
{
int i, j, max;
max = 0;
for(i = 0; i < 10; ++i)
for(j = 0; j < 20; ++j)
if (val[i][j] > max)
max = val[i][j];
printf("\nThe maximum array value is %d\n", max);

return;

}

These are the compiler errors I receive:
Error E2268 <filename> 10: Call to undefined function 'printf' in function findmax(int (*)[20])

Please help. I have looked through everything I have and can't figure it out. Also, How would you display the row and column number of the element w/ the max value?

jlliagre · 07-24-2004, 12:25 AM

Perhaps are you missing an include file.
You also seem to have overlook the hints given ...

ripwheels8 · 07-24-2004, 12:41 AM

Or I posted the wrong question for the code I had since I am an idiot. Here is the question for the code I have posted above:
Write a function that finds and displays the maximum value in a two-dimensional array of integers. The array should be declared as a 10-by-20 array of integers in main().

The code I have:
This is my code:

void findmax(int val[10][20])
{
int i, j, max;
max = 0;
for(i = 0; i < 10; ++i)
for(j = 0; j < 20; ++j)
if (val[i][j] > max)
max = val[i][j];
printf("\nThe maximum array value is %d\n", max);

return;

}

Also wondering how to display the row and column number of the element w/ the max value. Thanks for putting up with my stupidity.
Mike

osvaldomarques · 07-24-2004, 01:02 AM

Hi ripwheels8,
The compilation syntax error you have is because you need to add the line

Code:

#include <stdio.h>

in the top of your source code. The compiler needs to know the prototype of the function "printf", which is declared in "/usr/include/stdio.h".
Besides this, reading the source of your function, we can see that it is a routine to find a maximum value in the array it receives as parameter. There is nothing to do with your home work.
To display the row and column of your array in the function you post, you need to already save the values of the indexes you are using when you get the maximum values. So, instead of

Code:

if (val[i][j] > max)
  max = val[i][j]

you have to

Code:

if (val[i][j] > max) {
  max = val[i][j];
  max_i = i;
  max_j = j;
}

Then when you print the result you will have these values safe. Of course, you have to declare the variable max_i and max_j on the top of the function. Two more considerations: when you submit code, use the vBcode this site has. Its hard to examine a code as an edited text. You can read about vBcode in this site faq. That was the first consideration. The second is: read carefully the problem you are submitted to until you understand before start writing some code.
I hope this helps you. Have a nice week end!

ripwheels8 · 07-24-2004, 01:25 AM

Thank you!! Hope you have a pleasant weekend as well.