Thread: Need help: sorting random numbers rand() to odd and even in C

ive been tryin to figure out how to program this for nearly 6 hours straight no joke. still i couldnt. Basically i just want to create a program that can separate odd and even numbers from the generated random numbers and then storing it to the array.

my code so far..
btw im using linux emacs for this

Code:

#include <stdio.h>
#include <stdlib.h>

int main()
{
   int arr[10];
   int ran_num, i, eve_num, odd_num;

  srand(time(0));

  for(i = 0; i <= 10; i++)
    {
       ran_num = (10.0*rand()/(RAND_MAX+1.0));
       arr[ran_num]++;
     }

    if (arr[ran_num] %2 == 0)
       {
          printf("%d\n", arr[ran_num]);
          eve_num++;
       }
    else
       {
          printf("%d\n", arr[ran_num]);
          odd_num++;
       }

     printf("Even No.s : %d\n", eve_num);
     printf("Odd No.s  : %d\n", odd_num);

return 0;

}

I also tried swaping codes .. i gave everything i got but still it wouldnt work. I also tried inserting the IF Else statement inside For and its giving me wrong answer too.

Do you have to save the numbers into the array. Just expand your for loop the go around your if statements and every time you use arr[] replace it with ran_num.

This would be my first C program. I am not very familiar with syntax so... this is code is very far from elegant.
I am sure there are many things you could change and make it more readable/better looking.

If you do not understand any part of my code feel free to ask.

Code:

#include <stdio.h>
#include <stdlib.h>

int main(){

   int e=0;  /* counter for the even numbers  */
   int o=0; /*counter for the odd numbers    */

   int i, eve_num[10], odd_num[10]; /* evn_num/odd_num are size 10 arraies where we are going to write even/odd numbers. i is loop counter   */
   int ran_num=0; /* random number holder. You might want to switch from int to unsigned int. up to you  */

  srand(time(NULL));

  for(i = 0; i <= 10; i++){   /* for loop where we randomly choose 10 numbers  */

       ran_num = rand();


     if (ran_num %2 == 0){     /* nested loop in case we get even number  */
           eve_num[e] = ran_num;   /* place the even number into the array. e is array location counter that we update on next line  */
           e++;
     }

     else{                    /* same idea as above. However, for odd case   */
           odd_num[o] = ran_num;
          o++;
     }
  }

  int ev =0;
  for(ev; ev<e ;ev++){      /* loop where we are going to print the array that contains even numbers  */
          printf("Even No.s : %d\n", eve_num[ev]);
  }

  int od =0;  /* loop for printing odd numbers */
  for(od; od<o; od++){
     printf("Odd No.s  : %d\n", odd_num[od]);
  }


 return 0;

}

Set ran_num = rand();
Then do something like this:

Code:

if (ran_num % 2 == 0)
{
printf("%i\n", ran_num);
eve_num++;
 }
else
{
printf("%i\n", ran_num);
odd_num++;
 }

Then print out eve_num and odd_num.

If you want to have a random num 1-10 do something like this:

Code:

ran_num = rand() % 10 + 1;

Then change the 10 to the max num you want to use.

Originally Posted by dachichk

This would be my first C program. I am not very familiar with syntax so... this is code is very far from elegant.
I am sure there are many things you could change and make it more readable/better looking.

If you do not understand any part of my code feel free to ask.

Please don't just haul off and post complete solutions like that. You may put a smile on the OP's face but you totally deny them any chance of learning anything about programming. He's learned nothing of process or procedure... all he really knows from you is how to copy and past (scoop and poop) code for his own homework...

Plus there are errors in your code.

The OP pretty much has everything that i posted. I don't want to give everything for that very reason. Also, what is wrong with what I posted...it worked with no errors for me.

Originally Posted by rmatze

The OP pretty much has everything that i posted. I don't want to give everything for that very reason. Also, what is wrong with what I posted...it worked with no errors for me.

Wasn't talking to you... was talking to dachichk.... unless you are using two accounts, which is prohibited here.

Originally Posted by CommonTater

unless you are using two accounts

That could get weird if I had split personalities and one personality was helping the other code.

Originally Posted by rmatze

That could get weird if I had split personalities and one personality was helping the other code.

Trust me, I've seen FAR worse than that in my days...

At one point (on a different forum) we caught out one user with more than 10 accounts all of which were being used to attack one happless soul.

Originally Posted by CommonTater

Trust me, I've seen FAR worse than that in my days...

At one point (on a different forum) we caught out one user with more than 10 accounts all of which were being used to attack one happless soul.

Wow, must have really had it out for that person.

Originally Posted by rmatze

Wow, must have really had it out for that person.

Yes, there are some really sick __cks out there.

Hi guys, thanks for replies. Basically what ive been tryin to achieve is to generate 10,000 numbers

thats why im using

Code:

  for(i = 0; i <= 10; i++)
    {
       ran_num = (10.0*rand()/(RAND_MAX+1.0));
       arr[ran_num]++;
     }

and store it to the array and then divide them to even and odd

Code:

    if (arr[ran_num] %2 == 0)
       {
          printf("%d\n", arr[ran_num]);
          eve_num++;
       }
    else
       {
          printf("%d\n", arr[ran_num]);
          odd_num++;
       }
 
     printf("Even No.s : %d\n", eve_num);
     printf("Odd No.s  : %d\n", odd_num);

i know the logic but im consfused to write it in codes