help please i have errors and dont know how to fix them new at this

so im new to the c programming thing but im starting to find it quite intesting so i am trying to make a program that converts mph to fps but i keep getting errors can anyone help me heres the program

Code:

---

#include <stdio.h>
#include <math.h>

int main()

{

int mph =0
double fps, increment
printf("please input increment between 0-80 mph \n");
scanf("%lf", &increment);
mph=mph + increment

while mph <=80

fps=mph*5280/3600
printf("%5.0f %5.1f" \n, mph, fps);

}

---

i get errors on lines 12 saying that i have a syntax error before double
line 14 says increment is undeclared (first use this function)then on 14 again sainf that each undeclared identifier is reported only once for each function it appearsin.) and lie 17 says syntax error before "mph"

You need to terminate your line(s) with semi-colons ( ; )

And you need to look up how while loops work.

Code:

---

while (condition is true)
{
    /* run this code */
}

---

In your case, a for loop is likely a better option:

Code:

---

for(mph = 0; mph <= 80; mph += increment)
{
    /* run this code */
}

---

also while loop should be like

Code:

---

while ( condition )
{
  statement_1;
  ...
  statement_n;
}

---

ok thank guys

but what do i do about that syntax error on line 12

and line 17 increment undeclared and the syntax before ")" token whatever than my mean my c book isnt helpin me much with debugging

and my error in "main"

Well, show us your updated code. So that we could have a look at. And I also notices this in the printf statement:

Code:

---

printf("%5.0f %5.1f" \n, mph, fps);

---

The '\n' character is an escape sequence character, which would always be part of a string. So that should be within the double quotes. Like

Code:

---

printf("%5.0f %5.1f \n", mph, fps);

---

And you should also look at how to indent you could. May be you will start loving your own code ;)

Post your updated code. Let us see what have you got so far?

edit: Every statment in C language should terminate with the ';'. Make a note of that. So you write a code and thats SHOULD end with the ';' unless its some sort of conditional function!

-ssharish

Quote:

---

Originally Posted by ssharish2005

edit: Every statment in C language should terminate with the ';'. Make a note of that. So you write a code and thats SHOULD end with the ';' unless its some sort of conditional function!

---

What that last bit means is that

Code:

---

if (x) ;
    printf("x is true\n");

---

is "not right" - however, the compiler will happily compile it, and only few compilers will even say things like "Huh? did you mean to do "if (x) then do nothing" - it is not uncommon that even experienced programmers make that mistake from time to time. It gets extra bad when the condition is false only rarely - say in the above that we expect x to be true most of the time. It may be hard to discover that it has printed an extra "x is true" line for the time x was NOT true.

--
Mats

I did actually specify "unless it is some sort of conditional function. All other statments should end with the ';'.

Quote:

---

Originally Posted by ssharish2005
edit: Every statment in C language should terminate with the ';'. Make a note of that. So you write a code and thats SHOULD end with the ';' unless its some sort of conditional function!

---

Edit: May be i could have made much more clear ;)

-ssharish

You forgot a semi colon, another way to write it would be:
mph += increment;

Quote:

---

Originally Posted by magic3663

so im new to the c programming thing but im starting to find it quite intesting so i am trying to make a program that converts mph to fps but i keep getting errors can anyone help me heres the program

Code:

---

#include <stdio.h>
#include <math.h>

int main()

{

int mph =0
double fps, increment
printf("please input increment between 0-80 mph \n");
scanf("%lf", &increment);
mph=mph + increment          <----  need a semi colon,

while mph <=80
{
      fps=mph*5280/3600
      printf("%5.0f %5.1f" \n, mph, fps);
}

---

i get errors on lines 12 saying that i have a syntax error before double
line 14 says increment is undeclared (first use this function)then on 14 again sainf that each undeclared identifier is reported only once for each function it appearsin.) and lie 17 says syntax error before "mph"

---

Quote:

---

Originally Posted by madmax2006

You forgot a semi colon

---

Or a few... Which has already been discussed.

--
Mats

>You forgot a semi colon
there is more than a semi colon, which the OP has to sort out.

-ssharish

He was asking specifically what was wrong with that line (or close to there)......

thanks everyone for your help ill keep you updated ill post what i have so far hopefully it works

this is the code up date

Code:

---

#include <stdio.h>
#include <math.h>

int main()

{

int mph =0
double fps, increment
printf("please input increment between 0-80 mph \n");
scanf("%lf", &increment);
mph += increment;         

for ( mph <= 80; mph += increment );
{
      fps=mph*5280/3600
      printf("%5.0f %5.1f \n", mph, fps);
}

---

Errors:
in function main
12 syntax error before "double"
14 "increment" undeclared (first use in this function)
14 (Each undeclared identifier is reported only once for each function it appears in.)
17 syntax error before ")" token
19 "fps" undeclared (first use in this Function)
22 syntax error at end of input

Well, how many times should we have to point you out? Where are the semi-colns ????

Code:

---

#include <stdio.h>
#include <math.h>

int main()
{
    int mph =0 ;
    double fps, increment ;
    printf("please input increment between 0-80 mph \n");
    scanf("%lf", &increment);
   
    mph = mph + increment;
   
    for ( mph <= 80; mph += increment ) ; <-- why do you need this?? take this out   
    {
      fps=mph*5280/3600 ;
      printf("%5.0f %5.1f\n", mph, fps);
    }
    return 0;
}

---

ssharish

You are still missing several semi-colons at the end of statements.

The only lines that should NOT have a semicolon at the end are:

• Lines that start with #.
• Function definition name [e.g. main()] and the arguments to functions if they are on separate lines.
• Comments.
• Lines using keywords do, while, if, for [excepf it you write code like this:
  
  Code:

  ---

  if (x) y = 1;

  ---

• Lines that contain braces [assumimg you put braces on their separate lines - which is a good thing to do].

I've probably missed out one or two - but the concept is "most lines end with semicolon", some don't. [Ok, so technically, the LINE isn't ended with a semicolon, the statement is. But unless you have complicated/long statements, e.g. long calculations, a statement is the same as a line.

And you are missing some, and that's confusing the compiler - a bit like saying "Turn right at the big tree", when someone has cut down "the big tree", you'd get pretty lost when you turn at the next big tree you see - which is obviously not where you were supposed to turn. In this case, the compiler expects a semicolon at some point - but it finds the next "thing" - and the compiler doesn't quite know what is wrong, just that "This doesn't look at all like what I expected to see" - just like what would happen if you turn "a big tree later".

--
Mats

Code:

---

for ( mph <= 80; mph += increment ) ; <-- why do you need this?? take this out

---

orbetter move it inside brackets :P)

for needs 3 statements

Code:

---

for(mph=0 ; mph <= 80; mph += increment )

---

you can leave out first statement
you cannot loose the ;