a simple question about do while statement and choice options

[MyRedz]

i want to do a program that requires user to input float numbers,characters like this

printf("please enter the value with its SI unit...");
scanf(" %lf %c",&value,&si);
 

but then there is an escape statement thats says or q to quit ..
so i assume it needs units or character to quit...
but then how to integrate it with my normal asked input like the first..



i assume this but dunno of its compilabilty

 
 
#include<stdio.h>
 
char choice;
float value;
int main()
 
{
 
do{
printf("this is a program by ME\n);
printf("please input values followed with its SI unit or q to quit..\n);
scanf(" %lf %c"&value,&choice);
}while(choice!=q)
printf("have a nice day\n");
 
return 0;
 

i don't get is the q to quit..how can it be read only by itself because there is a float value with it???
any help???

[JosAH]

Lexical analisys of manual user input is quite complicated. Better read an entire
line first and process it later; if the sscanf(buffer, "%f %c, &f, &c) function call
doesn't return 2 it couldn't parse a float number and a character; next you could
try to process the line as sscanf(buffer, " %c", &c) and check whether or not c
contains the value 'q'. Don't forget to sprinkle in ample prompts because those
users never seem to understand what they've been asked to do.

kind regards,

Jos

[newb16]

You need to scanf it using "%s" specifier ( ok I know it is prone to buffer overflow ) like

 char buffer[100];
scanf("%s", buffer );
 

Then check it if it is equal to "q" string using strcmp, if yes then quit, else try to convert this string to float using sscanf.

[whodgson]

The 'q' is not in with the float it is separated from the float by a comma.
All that is apparently needed is some code like:

if(choise='q') return:

[r035198x]

The 'q' is not in with the float it is separated from the float by a comma.
All that is apparently needed is some code like:

if(choise='q') return:

= != ==