array question

[meteor]

Hi!

how do I send this array to a function to determin wich of
the texts who contains most characters

int main(){

char text[4][20] =
{
"hello",
"hello 2",
"hello 2 u",
"hello 2 u 2"
};

return 0;
}

[HairyDave]

You could declare a function:

int myFunction(char **array)
{
  // Do some stuff in here:
  if(strcmp(array[0], "hello") == 0)
    ....
  return 9;
}

Or something like that. If the array is constant you could declare it globally so it would be accessible from anywhere - but I expect that it isn;t always the same.

HD

[meteor]

Ive tryed this now.. but it doesnt work?!

#include <iostream.h>
#include <string.h>

int myFunction(char **array);

int main(){

char text[4][20] =
{
"hello",
"hello 2",
"hello 2 u",
"hello 2 u 2"
};

int a = myFunction(text);

return 0;
}


int myFunction(char **array)
{
// Do some stuff in here:
if(strcmp(array[0], "hello") == 0){

}

return 9;
}

[HairyDave]

What do you mean "it doesn't work"? When you say that try to give more details.

Are you using the string class - or just the string manipulation routines (strcmp, strcpy etc)? If you're using strings then the array problem is just 1-dimensional as you can declare an array of strings.

I am assuming the problem is with the conversion from char[4][20] to char **..?

Sorry about that - you need to declare the functions as

int myFunction(char array[][20])

You have to declare one of the dimensions for the compiler to like it.

HD

[CornedBee]

Here's correct code:

#include <iostream>
#include <cstring>
#include <cstdlib>
using namespace std;

int maxchars(char ** arr, int length);

int main(){

char text[4][20] =
{
"hello",
"hello 2",
"hello 2 u",
"hello 2 u 2"
};

int a = maxchars(text, 4);

return 0;
}

int maxchars(char (*arr)[20], int length)
{
  int m = 0, i, l;
  for(i=0; i < length; i++) {
    l = strlen(arr[i]);
    m = max(m, l);
  }
  return m;
}

Here's better code:

#include <iostream>
#include <string>
#include <algorithm>
using namespace std;

class pred_strlen {
public:
  bool operator ()(const string &s1, const string &s2) {
    return s1.length() < s2.length();
  }
};

int main(){
  string text[4] = {
    string("hello"),
    string("hello 2"),
    string("hello 2 u"),
    string("hello 2 u 2")
  };

  int a = max_element(text, text+4,
    pred_strlen())->length();

  return 0;
}

The code is better because it uses STL algorithms and the C++ string class.

[HairyDave]

I agree - but I wasn't sure that this was allowed - plus I don't know them very well

HD

[parksie]

If the question is as you said above, then the code given is about as correct as you can get in C++.

If your teacher complains, as I've said before, send them here

[meteor]

OK!!

Thanks for your help...