The Big Programming Thread - Page 115

On February 09 2012 00:15 Inori wrote:

When I wrote the suggestions, I assumed esotericc had extensive knowledge in programming since he said he freelancer for a few years. 2 months is more than enough when all you need to learn is syntax, idioms and distinctive features.

esotericc, since you actually don't have enough experience, I suggest ignoring my previous response and follow mmp post.

On February 10 2012 07:26 Frigo wrote:

Read Clean Code: A Handbook of Agile Software Craftsmanship, I doubt you will find that in tutorials.

On February 10 2012 07:26 Frigo wrote:

Read Clean Code: A Handbook of Agile Software Craftsmanship, I doubt you will find that in tutorials.

On February 10 2012 06:31 silentsaint wrote:
Does anyone know a good book about c#?

On February 10 2012 16:34 silentsaint wrote:


Thanks a lot. I'll look into it :-)

27 [Warning] passing arg 1 of `strcpy' makes pointer from integer without a cast

On February 11 2012 03:55 ranshaked wrote:
C Programming
Hey guys, I'm trying to find an explaination on pointers etc. I keep getting errors like this

Basically what I'm trying to do is the following: Take a few words and associate them with a number. Then compare the words and print the highest word (by its number)

Right now since it's homework, I'm only allowed to use 1D array and not 2D. I'm struggling with understanding how when a user inputs a word, followed by a number IE: scanf("%s %d", WORD, number);
It keeps saving only the last word and number that was entered. When I use my if statement
if (word >mostword)
{mostword=word;
strcpy(lrgstword, word);

I'm not exactly understanding how this stuff works, and after researching for a few hours I've decided that most of it points toward C++ and using other commands that I'm not allowed to use.

Obviously the assignment is much more complicated than this, but this is kind of what I don't exactly understand.

Edit: It would be like entering the following:
Corolla 5000
Mercedes 50000
Corvette 40000

Then it saves those values to each word (car) and compares them. I cannot get it to save to a 1D array :/

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[])
{
  char* stringCollection[5]; // An array of 5 character pointers....
  
  for ( int i = 0; i < 5; i++ )
  {
      stringCollection[i] = (char*)malloc(sizeof(char)*20);  // we're allocating memory to store stuff in our charater array.
      
      // ghetto if statement just to make example clear, do not code like this....   
      if ( i == 0 )
           stringCollection[i] = "Sup dawg how you doin??";
      else if ( i == 1 )
           stringCollection[i] = "Hello this is streing 2!!!";
      else if ( i == 2 )
           stringCollection[i] = "Yoyoyo i got the beats just call me dr. dre";
      else if ( i == 3 )
           stringCollection[i] = "C programming is AWESOME!";
      else if ( i == 4 )
           stringCollection[i] = "My Last String!!!";
  }
  
  // now let's print all this out!!!
  
  for ( int i = 0; i < 5; i++ )
    printf("String number %i: %s \n",i+1,stringCollection[i]);
    
  // Ironically, we can access specific element ( i.e characters ) of each string by using double array notation!!
  // That's because it is a double array!!!
  
  char myChar = stringCollection[0][5]; // the fifth element of the 0th string in the collection... in other words the "a" in "sup dawg..."
  char myChar2 = stringCollection[0][6]; // the sixth element of the 0th string in the collection...
  printf("myChar is: %c \n",myChar);
  printf("myChar2 is: %c \n",myChar2);
  
  system("PAUSE");	
  return 0;
}

On February 11 2012 05:03 Abductedonut wrote:


This would be practically impossible in C the way your teacher wants it. I think your confusion is here:

There are two "types" of strings in C and C++. There are c strings, which are declared the following way"

- char[] kitten = "You suck";
- char* kitten = (char*)malloc(sizeof(char)*50);
kitten = "You Suck";

Then there are C++ strings, which are declared like this:

- string kitten = "You Suck";
- string kitten2("You Suck");

What's the difference? Non perfectly speaking, c strings are basically character arrays. They can be declared without including any sort of header file. The nice people are Bell Labs wrote a file with a bunch of functions that do common manipulations on c strings, such as the lovely strcpy() that you're using. That is in <string.h> or <cstring> if you're in c++. C strings are not objects, they are basically raw character data. C++ strings, on the other hand, are objects from a class called the string class. That's why you MUST include <string> whenever you declare them.

So now... if we want to store multiple C strings... then we must have an array of c strings. However, c strings are in themselves arrays, which means you're "sortof" using a double array. I'll write some example code for you to see what I mean.

+ Show Spoiler +

It would be almost impossible to store c string without using a double array. I can't think of anything. If you're using strings, however, it's TECHNICALLY an array of objects and not a double array.

One way to do so is this:
- string myString[3] = {"Audi", "BMW", "Ford"};

That should give you a good start! I think your problem with strcpy(), btw, is that you're passing an integer for the first argument. You must pass a char* as the first argument. Ask yourself of what type "lrgstword" is. Hope this gives you some insight. Let me know if you have more questions.

On February 11 2012 05:32 tofucake wrote:
that's because it's pseudocode.

Also, you can convert strings/integers with atoi and itoa.

On February 11 2012 05:08 ranshaked wrote:

Thank you very much, I'll continue to read this. I knew that you can't force an integer to a string, but that's how he wanted it? I'm not quite sure. The actual homework question is pretty basic, but the way it is written and the example he gave doesn't even work. We've never used char * in any examples, which is partially why I'm confused.
+ Show Spoiler +

That was a "piece" of the code that he wrote down as we went over it in class. It doesn't work at all

On February 11 2012 08:55 Bobbias wrote:
What he's describing is basically keeping a "running maximum" for the input number, and copying the word you typed on the same line over into a variable whenever the number is larger than the previous one. Instead of storing each input and acting on them after, this is a sort of a filter that simply throws out anything smaller than the current largest number and saves the number and the associated word when it finds an input that is larger than it's current contents.

Personally my first instinct would have been to create a 2 dimensional array, feed each new line in and then process, but with the limitations you have, what he's describing there sounds like a pretty good way to go about it.

On February 10 2012 06:47 Kasha_Not_Kesha wrote:
Programming books are very rarely worth the money. If you're trying to teach yourself how to program in a specific language, it's usually easier and cheaper (and more beneficial in the long run) to look up tutorials online. That's my opinion anyway =P

On February 11 2012 09:57 tec27 wrote:

Its not just a pretty good way to go about it, its pretty much the *best* way to go about it. It avoids double-iterating the list and avoids allocating a large chunk of memory to store all the strings that it will only look at once. Much better than the naive approach, especially for large input sets.

On February 10 2012 23:19 Neelia wrote:


C# in Depth (Jon Skeet) and CLR via C# (Jeffrey Richter)

If you know the basics.

On February 12 2012 01:23 billy5000 wrote:
speaking of books, can anybody recommend me a good intro java book, specifically with numerous exercises? the book we use for class does in fact has tons exercises, but no answers (wtf??). Some of them you can check for yourself, which i have no problems with, but other questions ask for a fragment code from a more complicated whole and such.