Checking an input lenth and content

[whity4420]

I am trying to write a script that will only allow even inputs from 2 to 98. If the user inputs an incorrect value or characters it should ask them to input the values again.

Can anybody help me with this?

I know how to check the length or if the characters are correct but can not figure out how to do both.

Thanks, Tom

[mike_g]

If you know how to check the length and you know how to check the validity of the characters, why not do one check after the other?

[whity4420]

I can but then if i ask them to input again after checking the second time I need to check again and so on untill i have a lot of repeating code...

I think.

Unless im thinking about it totaly wrong. I need to always ask and validate untill they input the correct value.

#include <stdio.h>

int main( void )
{
    char number_res[1000];
    int temp;


    printf( "enter number of resistors\n" );
    scanf( "%s", number_res );



    while(number_res[temp] < 48 || number_res[0] > 57 || number_res[1] < 48 || number_res[1] > 57){
            printf( "Please enter numbers \n" );

            printf( "enter number of resistors\n" );
            scanf( "%s", number_res );
        }
              
    
    

    printf("Number was %d\n", atoi(number_res));

    return 0;
}

[tabstop]

You have a number_res that needs to be even and between 2 and 98 inclusive, right? So something like

while (isOdd(number_res) || isNegative(number_res) || is100OrBigger(number_res))

This then becomes a question of checking each condition. Note that the idea is you do all three checks with the same input before asking again.

[whity4420]

Ah.

Thanks!

I was just trying to do somthing utterly pointless and making life much more difficult for myself.

Thanks again.

[Elysia]

whity4420, please have a look at https://apps.sourceforge.net/mediawi...tle=Scanf_woes regarding scanf.