AP-GP problem solving?

#include
using namespace std;
int main()
{int a1, a2, a3;

LOOP:cin>>a1>>a2>>a3;
while(a1!=0 && a2!=0 && a3!=0)
{

if((a2-a1)==(a3-a2))
cout<<“AP “<<(a3+(a3-a2))<<”\n”;

if((a2/a1)==(a3/a2))
cout<<“GP “<<(a3*(a2/a1))<<”\n”;

goto LOOP;
}

return 0;

}

Whats the problem with this code?

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