#include <stdio.h>
struct A {
  int c;
  int x(int a, int b);
  static int y(int a, int b);
  A(int x) : c(x) {}
};
int A::x(int a, int b) { return a * b * this->c; }
int A::y(int a, int b) { return a * b /* * this->c */ ; } // 'this' is unavailable for static member function
int main(void) {
  A a(5);
  printf("%d", a.x(2, 3));
  printf("%d", a.y(2, 3)); // *** why can we call this way ? ***
//  printf("%d", A::x(2, 3)); // cannot call member function
  printf("%d", A::y(2, 3));
  return 0;
}

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