simple help needed

[afromong]

Hi if i want to say if (int <= 0 || int is not a number)

how could i do this i want to make sure that a positive number is input not a negative number or word or symbol hope this makes sense

[ddanbe]

Use the scanf function with a conversion specifier.
scanf("conversion specifier", variable);
%d means integer
%f means floating point munber
%c means any character input
Example : scanf("%d",i);
The variable i will contain only digits.

[sidatra79]

hi

Use the scanf function with a conversion specifier.
scanf("conversion specifier", variable);
%d means integer
%f means floating point munber
%c means any character input
Example : scanf("%d",i);
The variable i will contain only digits.

Correct solution but for the C language.... Works for C++ too though.

I would propose:

cin.ignore(numeric_limits<int>::max(), '\n');

the C++ way of saying 'the largest possible integer number'

I know it looks ugly.... :D

[ArkM]

Alas, ddanby's "solution" is absolutely incorrect. Must be

if (scanf("%d",&i) == 1 && i > 0) { // OK
...
} 
else { // error or eof or <= 0

If you have a C-string str with text, test if it's an integer:

if (sscanf(str,"%d",&i) == 1 && i > 0) { // OK

As usually ;) sidatra79's "solution" does not bear a relation to the problem...

[WaltP]

Every solution proposed here has major problems -- that of trying to read an integer when a 'not a number' can be entered which screws up the entire read process..

You need to read an entire line as a string, test all characters entered up to the '\n' to make sure they are all digits. If they are, convert the string to an integer, if not, output an error.

[afromong]

thank you for all your help i will try these solutions