# Re: Structure Help

• 01-21-2002
cj348879
Re: Structure Help
Hey guys, I got this program assignment in class and I'm not sure how to start it. It needs to prompt the user to input a number and then checks each digit of the number to see whether it is a valid integer (ie. Characters are invalid). If it's not a number, it asks the user to enter another number, if it is a valid number, it outputs the number to the screen.
Now if anyone could help with with just the different functions and such I might use, that would be of great help. Below is what I've got so far.

//-----------------------------------------------------//
// NAME: Christopher Jackson //
// CLASS: CSC142-02 //
// SEMESTER: Spring 2002 //
// ASSIGNMENT: Program Assignment No. 1 //
//-----------------------------------------------------//

//----------------------------------------------------------------------------------------
// Program 1
// DESCRIPTION:
//----------------------------------------------------------------------------------------

#include <iostream>

bool digitCheck(string);
bool invalidChar();
void validOutput();
void invalidOutput();

//-----[ fUNCTION mAIN ]------------------------------------------------------------------

int main()
{
bool validString;
string number;
cout << "Please enter an integer: ";
cin >> number;

validString = digitCheck(number, validString);
output;

return 0;
}

//-----[ fUNCTION dEFINITIONS ]-----------------------------------------------------------

bool digitCheck(string num, bool vS)
{
for (count = 0; count <= 10; count++)
{
char currentChar = num[count];
if (count==0)
{
switch (currentChar)
{
case - :
case 0 :
case 1 :
case 2 :
case 3 :
case 4 :
case 5 :
case 6 :
case 7 :
case 8 :
case 9 : break;
default: invalidChar(vS); break;
}
}
else
{
switch (currentChar)
{
case - : invalidChar(vS); break;
case 1 :
case 2 :
case 3 :
case 4 :
case 5 :
case 6 :
case 7 :
case 8 :
case 9 : break;
default: invalidChar(vS); break;
}
}
}
vS = true;
return vS;
}

bool invalidChar(bool vS_)
{
vS_ = false;
return vS_;
}

void validOutput()
{
}

void invalidOutput()
{
}

//-----[ eND pROGRAM ]--------------------------------------------------------------------
• 01-21-2002
Leeman_s
ah yes
very nice function...:

int isdigit(num);
• 01-21-2002
Uraldor
or if you want to write your own

Code:

```bool IsDigit(char c) {   return(c >= 0x30 && c <= 0x39); } if(IsDigit(num[i]) || (i == 0 && num[0] == '-')) {   // valid number }```
hope this helps
U.
• 01-22-2002
Troll_King
Code:

```using System; class Cpp {         public static void Main()         {                 int number;                 Console.Write("Enter a number: ");                 try                 {                         number = Convert.ToInt32(Console.ReadLine());                         Console.Write("You entered: " + number);                 }                        catch                 {                         Console.WriteLine("Bad data exception.");                 }         } }```