Need help with a C++ program...

[[N]auTiCa]

Hey hows everyone been..?

Haven't been around the Q2 community for awhile and what better way
to come back then to ask for help 

Anyway, I'm having a bit of trouble with the following code.

You are to input 7 numbers then print, however if you input anything other than a number
higher than 7 it says it's to high. I need user input to type in any 7 numbers from 0-9
then print all 7 on one line. If they input more than 7, it's to give an error then exit.

Heres what I have thus far.

Code: [Select]

#include <iostream.h>

int main()
{
   const int x = 7;
   int count[x];
   int num;
   for (int num=0; num<7; num++)
   {
                     cout << "Enter exactly 7 numbers" << endl;
                     cin>>count[num];

                     if(count[num]>x)
                     cout<<"Too many numbers entered "<<endl;
                     else
                     cout << "\nThats it."<<endl;
                     cout<<"\ninputs: " << count[num] <<"\n";
                   
                   
                         
                   
        system("PAUSE");
    return(0);
}
}


Any help would be greatly appreciated.

p.s. hey console.. ltns

[opt1ckz]

if this is homework.. go read your book. understand how COUNT works and see if you can find any shortcuts to display 1-7. if you're too lazy to do that, go on http://www.google.com and search for it yourself. that's what a learning process is, not just asking people to do your homework for you.

[reaper]

I googled "enter number user input c++.

The snipper below just enters the input into a string.  Then characters in the string are referenced as array elements.  So '0' is the ascii value of the number 0 during the comparison.

I'm sure you could do it a few ways.

#include <string.h> // Don't forget the library that handles strings
 
string number; //declares string
int i=0;       //declares int for the loop
 
cout << "Enter a number : ";
getline(cin, number);    //Inputs number
 
while(i <= number.length()) //Loop that goes through all the letters
{
        if(number < '0' || number > '9') //Does the character have a ASCII value under 0 or above 9?
        {
                        cout << "\nThat isn't a number!!";
                        return 0;
        }
        i++; //If it passed the check above, then it's time for the next letter
}

[kren.Z]

Code: [Select]



#include <iostream.h>


int main()
{
   int count[7]; //elements 0 - 6
   int x = 0;
   int temp;
 

do
{


                     cout << "Enter number" << endl;
                     cin >> temp;

if(x>6)
break;

                     if(temp>7)
{
                      cout << "Too high." <<endl;
continue;
}

     else if(temp < 0)
{
cout << "too low" << endl;
continue;
}

else
{
count[x] = temp;
x++;
}

                   
}while(true);



for(int i=0;i<x;i++)
{

cout << " " << count[i];
}


system("PAUSE");
return 0;
                   


}


[[N]auTiCa]

thanks reaper and krenz.. that actually helped a lot.

as for this q2 noobie flamethread starter k_ ...if you have nothing useful to say, don't respond to my threads, so
just move along, cuz from here on out you will just be ignored.

had I just asked someone to do my hw, I would have posted a problem and asked for a solution, not provided
any code.

thanks again to the old q2'ers willing to help the infamous [N]auTiCa 

[opt1ckz]

thanks reaper and krenz.. that actually helped a lot.

as for this q2 noobie flamethread starter k_ ...if you have nothing useful to say, don't respond to my threads, so
just move along, cuz from here on out you will just be ignored.

had I just asked someone to do my hw, I would have posted a problem and asked for a solution, not provided
any code.

thanks again to the old q2'ers willing to help the infamous [N]auTiCa 

just saying you won't learn from asking other people for answers. good job being a douche bag.

[peewee_RotA]

just saying you won't learn from asking other people for answers.

Worst advice ever.


(although I agree with what you were trying to say but miserably, horribly, and undeniably failed at expressing)

[QwazyWabbit]

Hey hows everyone been..?

Haven't been around the Q2 community for awhile and what better way
to come back then to ask for help 

Anyway, I'm having a bit of trouble with the following code.

You are to input 7 numbers then print, however if you input anything other than a number
higher than 7 it says it's to high. I need user input to type in any 7 numbers from 0-9
then print all 7 on one line. If they input more than 7, it's to give an error then exit.

Heres what I have thus far.

Code: [Select]

#include <iostream.h>

int main()
{
   const int x = 7;
   int count[x];
   int num;
   for (int num=0; num<7; num++)
   {
                     cout << "Enter exactly 7 numbers" << endl;
                     cin>>count[num];

                     if(count[num]>x)
                     cout<<"Too many numbers entered "<<endl;
                     else
                     cout << "\nThats it."<<endl;
                     cout<<"\ninputs: " << count[num] <<"\n";
                   
                   
                         
                   
        system("PAUSE");
    return(0);
}
}


Any help would be greatly appreciated.

p.s. hey console.. ltns

It's a bit unclear to me what you are really trying to accomplish. You are initializing an array of 7 ints, (count[ x ], where x = 7, arrays always begin with index 0) and then you are accepting inputs to num but then your loop breaks on the first entry. You are also redefining num as int num in the loop after it was already defined as int in the local variables. Redefining variables this way is a Bad Practice at best and a fatal error to a proper C++ compiler.

Are you inputting 7 NUMBERS in 7 lines or are you inputting 7 digits on a line? If the latter, you don't really need the array. Also, the variable x is not needed unless you are intending to parameterize that value as a non-constant. You also put the prompt for 7 numbers inside the loop, causing it to be sent 7 times if the loop executes that many times, I am not sure that is your intent. Your return(0) is also in the wrong place, it should come after the closing brace of the for() loop.

You also have a potential buffer overflow: you cin>>count[num] and then test to see if num is greater than 7. If num were greater than 7 at that point, you would already have written user input outside the space allocated for the count array, clobbering any data nearby. Potentially fatal to your program or an intermittent bug to say the least.

All the solutions offered so far, while requiring C++ to implement, are not strictly C++ nor good examples of what you have described but failed to code. Kren.Z' solution covers the buffer overflow issue but prompts for corrections not described in your "specification" of what the module is supposed to do. Reaper's solution pulls in string.h (not proper C++) It should be <string>. Reaper also calls istream::getline without proper argument specifying the size of the buffer, leading to a potiential buffer overflow. Reaper's code also uses "ASCII" constants and modern C++ is Unicode or ought to be and strings are of type _T and you should forget all about ASCII and char arrays when writing C++ for portability.

Your choice of count, to receive the "numbers" but use of num to count the numbers left me feeling upside down.

All in all the whole thing left me a little confused about what you are really trying to accomplish.

[reaper]

Reaper also calls istream::getline without proper argument specifying the size of the buffer, leading to a potiential buffer overflow

#include <string.h> // Don't forget the library that handles strings
 
string number; //declares string
int i=0;       //declares int for the loop
 
cout << "Enter a number : ";
getline(cin, number);    //Inputs number
 
while(i <= number.length()) //Loop that goes through all the letters
{
        if(number < '0' || number > '9') //Does the character have a ASCII value under 0 or above 9?
        {
                        cout << "\nThat isn't a number!!";
                        return 0;
        }
        i++; //If it passed the check above, then it's time for the next letter
}

number is as big as the input from the user, so it's dynamic like using malloc.  when a user enters the a newline input will stop being read. you might enter in a billion lines of input, but then I think you got other problems, and the program would just crash.  I just copied the first piece of code on google, but it's still c++ even if it has some c functions

[QwazyWabbit]

Reaper, it looks like you never tested your sample. It won't compile as-is and the digit test always fails.

Here is a new program in valid C++ that does what Nautica described. It uses isdigit() from the C runtime.

Code: [Select]

#include <iostream>
#include <cstdlib>
#include <string>

using namespace std;

// this function receives user input as a string and checks
// for valid digits. If all valid decimal digits, return the string,
// else return an empty string.
string getnumber(void)
{
string number; //declares string
int i; //declares int for the loop

cin>>number;    // input a string

i = 0; // initialize loop variables close to top of the loop
while(i < number.length()) //go through all the letters except the termination character
{
if(!isdigit(number[i])) // are all valid digits 0 thru 9?
return "\0"; // invalid digit found, return empty string
i++;
}
return number; // return a valid number string
}

// call the getnumber function 7 times and print the results
int main(int argc, char *argv[])
{
int i;
const int maxnum = 7;
int count; //count the valid numbers returned
string number[maxnum];

count = 0;
for(i = 0; i < maxnum; i++)
{
cout << "Enter a number : ";
number[i] = getnumber();
if(number[i] == "\0")
{
cout << "That isn't a decimal number!!\n";
break;
}
count++;
}
cout<<"\n"<<i<<" valid numbers received:\n";
for (i = 0; i < count; i++)
cout<<number[i]; // print the numbers
cout<<"\n";
return 0;
}

This code is tested and works in OS/X, Windows and Linux.

[quadz]

Just fer fun... here's a ruby version:

Code: [Select]

numbers = []
while numbers.length < 7
  print "Enter a number: "
  input = gets.chop
  num = Integer(input) rescue nil
  if num.nil?
    puts "YOU FAIL!"
  elsif ! num.between?(0, 9)
    puts "Close but no prize."
  else
    numbers << num
  end
end

puts numbers.join(" ")


$ ruby numbers.rb
Enter a number: asd
YOU FAIL!
Enter a number: -1
Close but no prize.
Enter a number: 10
Close but no prize.
Enter a number: 0
Enter a number: 9
Enter a number: 2
Enter a number: 4
Enter a number: 3
Enter a number: 7
Enter a number: 4
0 9 2 4 3 7 4

[[N]auTiCa]

Although the first couple responses didn't do exactly what I was attempting, it did help understand what I was trying to accomplish.

As for the other responses... thanks QwazyWabbit, if you actually coded all that yourself, I'm quite impressed you took the time
to help me that much, I appreciate it. As a side note, I actually needed 7 inputs on one line, asked once to enter only 7 digits.
You said if that were the case I wouldn't need an array, but I don't see how I could accomplish this without an array?

As for quadz.. wtf is ruby? lol

/sarcasm

[QwazyWabbit]

In that case an arrayless version might be:

Code: [Select]

int main (int argc, char * const argv[])
{
string number;

cout << "Enter exactly 7 digits" << endl;
cin >> number;
if (number.length() > 7)
cout << "Too many digits!" << endl;
else
cout << number << endl;
}

The cin class only returns once the stream is filled by the user and the termination key is pressed. I have never used it to capture chars, but there may be a member of that class that can do that for you.  If that is the case you can copy char into the string array and loop while char is not "\n". Then evaluate the length of the filled string. Making the string number into an int number is left as an exercise for the student.

[QwazyWabbit]

As for quadz.. wtf is ruby? lol

"Ruby, don't take your love to town."

[[N]auTiCa]

Thanks QwazyWabbit on the arrayless version, I never thought of using arguments this way.