newb to C, cant figure something out.

i JUST started C a few days ago.

i decided, after reading a prog in a book i have, to make a program to either multiply or divide two ints depending on user input.

so i wrote the program, got like 14 compile errors, fixed most of em

now im down to 2-4 compile errors, and i just cant figure them out.

either they r too cryptic, or i just don understand yet.

here are the errors, if you need program source i will post:

c:\docume~1\galgar~1\desktop\untitl~1.cpp: In function `int main()':
c:\docume~1\galgar~1\desktop\untitl~1.cpp:17: parse error before `else'
c:\docume~1\galgar~1\desktop\untitl~1.cpp: At top level:
c:\docume~1\galgar~1\desktop\untitl~1.cpp:22: parse error before `return'



actually, here is source:

Code:

---

#include <stdio.h>

int num1, num2, num3, num4;
int product(int x, int y);
int divide(int z, int a);
int main( void )
{
  printf ("pick Multiply, divide(1,2):");
  scanf ("%d", &num4);
  printf ("enter a number:");
  scanf ("%d", &num1);
  printf ("Enter another number:");
  scanf ("%d", &num2);
  if (num4 == 1)
  num3=product(num1,num2);
  printf ("total multiplied is: %d",num3);
  else
  {
  num3=divide(num1,num2);
  printf ("total divided is: %d",num3);
  }
  return 0;
}
int product(int x,int y)
{
return (x*y);
}
int divide(int z, int a)
{
return (z/a);
}

---

please tell me what im doing wrong... i cant figure it out.


Thanks in Advance,
Phate

should be this

Code:

---

  if (num4 == 1)
  {
  num3=product(num1,num2);
  printf ("total multiplied is: %d",num3);
  }
  else
  {
  num3=divide(num1,num2);
  printf ("total divided is: %d",num3);
  }

---

"else statement without a matching if"

thnx a TON.

in my book, there was a code for just multiplying, but no if/else statements, so i looked farther in the book

for some reason it didnt have the brackets... whatever

thanks a ton for your help!,
Phate

program worked without a hitch! YEAH!!!

btw, is there a way to make it so if i doubleclick the icon on desktop, it doesnt just autoclose after user input is done?

as it is, i get this:

choose multiply or divide (1,2): 1
Enter a number: 10
Enter another Number: 2
(window closes faster then i can read next output)
The Numbers divided are: 5

is there a way for it to remain open until i choose to close it?

also, is there a way that i can make it start over? like after it did the calculation it would go back to choosing multiply or divide?

i know in C++ u can do a GO thing or whatever, but i dont know it in C

what is it, and where would i put it?

thanks a lot,
Phate

Quote:

---

btw, is there a way to make it so if i doubleclick the icon on desktop, it doesnt just autoclose after user input is done?

---

Throw in a getchar() at the very end of the program

Quote:

---

also, is there a way that i can make it start over? like after it did the calculation it would go back to choosing multiply or divide?

---

Stick a while loop over the mult/divide code.

Quote:

---

i know in C++ u can do a GO thing or whatever, but i dont know it in C

---

goto is frowned upon, the method is the same for c++, just a big while loop

what kind of while loop... like just type while above the first printf?

sorry, im REALLY noob. need things spelled out for me lol.

ok, i tried adding another int, Counter

inside int Main(void) i put the statements: Counter == 1, While (Counter < 1000) and put the program except return 0 in brackets, and put Counter ++ at the end

now im gettin compile errors again :(

here is the code:

Code:

---

#include <stdio.h>

int num1, num2, num3, num4;
int Counter;
int product(int x, int y);
int divide(int z, int a);
int main( void )
{
  Counter == 1
  while (Counter < 1000);
  {
  printf ("pick Multiply, divide(1,2):");
  scanf ("%d", &num4);
  printf ("enter a number:");
  scanf ("%d", &num1);
  printf ("Enter another number:");
  scanf ("%d", &num2);
  if (num4 == 1)
  {
  num3=product(num1,num2);
  printf ("total multiplied is: %d",num3);
  }
  else
  {
  num3=divide(num1,num2);
  printf ("total divided is: %d",num3);
  }
  Counter ++;
  }
  return 0;
}
int product(int x,int y)
{
return (x*y);
}
int divide(int z, int a)
{
return (z/a);
}

---

and the compile errors:

Code:

---

c:\docume~1\galgar~1\desktop\untitl~1.cpp: In function `int main()':
c:\docume~1\galgar~1\desktop\untitl~1.cpp:10: parse error before `while'
c:\docume~1\galgar~1\desktop\untitl~1.cpp:29: parse error before `}'

---

whoops. forgot ; after while and counters... that brings errors down to:

Code:

---

c:\docume~1\galgar~1\desktop\untitl~1.cpp: In function `int main()':
c:\docume~1\galgar~1\desktop\untitl~1.cpp:10: parse error before `while'

---

just assume in previous code that Counter ++ is now Counter ++; and While (Counter < 1000) is now While (Counter < 1000);

so what is wrong?

AHAHAHAHHAHA

just forgot ;s

its fixed now lol.

hmmmmm...

now when i compile i get NO errors... but when i RUN it, there is no text.

its just a blank screen.....

any ideas?

Just like you don't need a ; after your if statements you don't need a semicolon after your while statement. If you do put one it will simply repeat over and over again until Counter is less than 1000, which will never happen because there is nothing being executed in the loop. So, you need to remove that semicolon.
Also, you need to set Counter = 1; not ==. == is used for comparing two things, its easier to remember it as "is equals" because it it two equal marks.

this was my solution to program termination: i wrote a fucntion using the <time.h> header that waits for the specified number of seconds before it terminates, so that output can be seen before termination. If you need the code, I can get it to you.

this is the header file for this function:

Code:

---

#include <stdio.h>
#include <time.h>

/* function uses time.h to determine how long to wait */
 
void pause(int duration)
{
 int a, b;

 b = clock() / CLOCKS_PER_SEC;
 a = b + duration;

 while (b < a)
 {
  b = clock() / CLOCKS_PER_SEC; /* the function will wait until the # of secs is up */
 }
}

---

and here is a sample program I wrote. It should be ok for demostration purposes. Any questions, feel free to ask:

Code:

---

#include <misc.h>

main ()
{
 char cmd[5], exitcmd[5] = "exit";
main:
 for(;;)
 {
  printf(" Hello.\n ");
  pause(3);
  printf(" Would you like to exit? Type exit now\n");
  gets(cmd);
  if ((strcmp(cmd, exitcmd)) == 0)
  {
  return 0;
  }
  goto main;
 }
}

---

> Any questions, feel free to ask:
Ok, why are you using goto, and why are you using gets() ?

And why go through all that timer code? Why not just add at the bottom of main() before the return the following:

Code:

---

    cin.get();
    return 0;
}

---

for C++

Code:

---

    getchar();
    return 0;
}

---

for C

A simple and direct screen pause.

The "timer code" is a really bad idea because it thrashes the cpu in a busy wait by calling clock() over and over.