Syntax error in hailstones sequence program

[dttin27]

Hi, I'm trying to write a program that can generate some hailstones, here is my code so far:

#include<stdio.h>
#include<stdlib.h>
 
void    hailstones(int n);
int main(void)
{
        int a;
        printf("Enter the number: ");
        scanf("&d", &a);
        return 0;
}
void hailstones(int n)
{
        int i = 0;
        while (n != 1){
                if (n % 2 == 0) {
                        n = n/2;
                        printf("%d", n);
                        i = i + 1;
                }
                else (n % 2 != 0) {
                        n = (3 * n) + 1;
                        printf("%d", n);
                        i = i + 1;
                }
        }
        printf("Number of hailstones generated: %d\n", i);
}

The program returns some errors:
hailstones.c: In function `hailstones':
hailstones.c:20: error: syntax error before '{' token

Can anybody please tell me what I did wrong and what should I do to fix these problems?

[johny10151981]

whenever you use else you must not use any condition.

//this is wrong
else (n % 2 != 0) {
 
//right would be
else 
{
...
}
 

in your case you do not need to write the second condition at all. cause possible return is two 1) zero or 2) not zero

[Banfa]

You could use else if though

if (n % 2 == 0) {
  ...
}
else if (n % 2 != 0) {
  ...
}