1extern void sf ( __const char *);
2struct Matrix{
3  int operator[](int n){
4    sf ( __PRETTY_FUNCTION__);
5  }
6  int operator[](int n)const{
7    sf ( __PRETTY_FUNCTION__);
8  }
9};
10void calcmy(Matrix const &b, Matrix &c, int k){
11  b[k];
12  c[k];
13}
14