#include "iostream"
using namespace std;
int & f1(int x=0,int y)
{
return x*y;
}
int *f2(int a,int b=1)
{
int t=a*b;
return &t;
}
int main(int argc, char* argv[])
{
const r;
int &a,*p;
r=10;
a=r;
const char *pc1 = "dukang";
char *const pc2 = "dukang";
char const *pc3 = "dukang";
const char const*pc4 = "dukang";
pc1 ='t';
pc2[2] = 't';
pc3[2]='t';
pc4[2]='t';
cout<<f1(3)<<endl;
cout<<f2(2,3)<<endl;
return 0;
}