I am very new to programming in C, and can't seem to locate the cause of the segmentation error that I have been getting. The program I wrote is as follows:
# include <stdio.h>
# include <stdlib.h>
int recursive(int x){
if(x=0)
{
return 2;
}
else
{
return 3*(x-1)+recursive(x-1)+1;
}
}
int main(int argc, char *argv[])
{
int N = atoi(argv[1]);
return recursive(N);
}
I would appreciate any help.
Thanks a lot
if(x=0){...}
it's wrong
It should be
if(x==0){...}
Note:
if (x = 0)
is the same as:
x = 0; if (x)
This:
if(x=0){
is not a (pure) test, it's an assignment. It works in the if since it also has a value (zero), but it's always false so that branch is never taken, i.e. the recursion never stops.
You should enable all compiler warnings, this is very commonly caught by compilers.
Change if(x = 0) to if(0 == x)
It is a good rule of hand to write 0 == x instead of x == 0 because in case of a typo like = instead of == the compiler will give an error.
The segfault error is from the use of argv[1]. Make sure you call your function with an argument, as follow:
$ ./a.out 6
with a.out the name of your program, and 6 the number you want to apply the function on.
The following line will create a segfault :
$ ./a.out
because the first argument isn't set.
Plus, watch out on the second line : use == instead of =
if( 0 == x)