/* Pandigital number verifier Usage Example: Enter integer to check, the driver code uses a loop to allow accepting multiple inputs. LOGS: - Changed default processing to use the string version to cope with long long type limit. - Changed the frequency counter to use vector (previously used array). [ Suggested by @~ swim ~] © 2018 SoloLearn Community */ #include #include #include #include // Flag masks, used to verify digit presence. const int flagMask[10] { 1, 2, 4, 8, 0x10, 0x20, 0x40, 0x80, 0x100, 0x200 }; /* Function isPandigital Description: Verifies a number is a pandigital number. Parameters: ll The number vector Digit frequency counter Return value: bool, true when input is a pandigital number. bool isPandigital( long long n, std::vector& freqStat) { // Zero fill digits counter for(int i = 0; i < 10; freqStat.at(i) = 0, i++); // * Negative values will be reversed to // anticipate minus remainder from % // operation, we need positive value for // and array index. // // * Any number having less than 10 digit // will be considered unfit, it needs 10 // digits to fit all 0-9. if(n < 0) n = -n; if(n < 1000000000LL) return false; size_t r, flag {0}; // Extract each digit, increment their // counter, mark the presence of a number // by OR-ing the flag with . while(n) { r = n % 10; n /= 10; freqStat.at(r)++; flag |= flagMask[r]; } return flag == 0x3ff; } */ /* Function isPandigital (string version) Description: Verifies a number is a pandigital number. Parameters: string Numeric string input vector Digit frequency counter Return value: bool, true when input is a pandigital number. */ bool isPandigital( std::string nStr, std::vector& freqStat) { // Zero fill digits counter for(int i = 0; i < 10; freqStat.at(i) = 0, i++); // [ Input Validation ] // * No blank input is allowed // * Zero lead input do not fit. // * Discard negative sign off input. // * Input with < 10 digits do not fit. if(nStr.empty()) return false; if(nStr.at(0) == '0') return false; if(nStr.at(0) == '-') nStr.erase(0, 1); if(nStr.length() < 10) return false; size_t r, flag {0}; bool valid {true}; // Check each character for numeric value, // increment counter for numeric ones, and // mark the presence of a number by OR-ing // the flag with . for(char digit : nStr) { // Stop processing if there is a non // numeric character in the input. if(!std::isdigit(digit)) { valid = false; break; } r = digit - 48; freqStat.at(r)++; flag |= flagMask[r]; } return valid && (flag == 0x3ff); } // Main procedure int main() { std::vector counter(10); //long long input; std::string input; std::cout << "Enter an integer:\n\n"; while(true) { std::cin >> input; if(!std::cin.good()) break; if(input.empty()) continue; std::cout << input << " is "; if(isPandigital(input, counter)) { std::cout << "Pandigital number.\n\n"; std::cout << "Digit frequency (times):\n"; for(int i = 0; i < 10; i++) { std::cout << i << ":" << counter[i] << " "; if(i == 4) std::cout << "\n"; } std::cout << "\n\n"; } else std::cout << "not Pandigital number.\n\n"; } }

Challenge - Pandigital Numbers