Floating point exception (core dumped) please fix it ExtendedEuclid pblm

#include<bits/stdc++.h>
using namespace std;
int gcd(int a,int b )
{
if(b==0){
return a;
}
return gcd(b,a%b);
}
int x,y,GCD;
void extendedEuclideanGCD(int a,int b){
if(b==0){
x=1;
y=0;
GCD=a;
}
extendedEuclideanGCD(b,a%b);

int Cx,Cy;
Cx=y;
Cy=x-(a/b)*y;
x=Cx;
y=Cy;

}

int main()
{
extendedEuclideanGCD(18,30);
cout<<x<<" "<<y<<endl;
return 0;
}

https://ide.codingblocks.com/s/46625

I have made a small change.