How do I write this code? C++

#include #include using namespace std; int calculateFrequency(int num, int d); /** * Requires: pin has no leading zeros * Modifies: nothing * Effects : (1) returns false if pin has less than five digits; (2) returns false if pin has more than five digits; (3) returns false if pin has a repeating digit; (4) returns true if pin contains exactly five non-repeating digits; **/ bool isValidPin(int pin) { // TODO: implement // NOTE: return false to avoid compile eri error // remove it after implementing return false