/* ***** Usage example (Code Playground) ***** Enter each sample username to check separated by new line. For detailed info call checkUserName in main function passing true as the second argument, following the variable. ******************************************* Function checkUserName. Description: A function to verify username. The function checks for the following criteria: 1. String has at least an uppercase letter [3] 2. String has at least a lowercase letter [3] 3. String has at least a number. 4. String has at least one of the required character (@#*=) 5. String length minimum 5 and maximum 10 characters. 6. String must not contain space. Parameters: 1. string (username) to test. 2. bool Verbose mode @true: Displays statistics. @false: Only displays validation status. 3. bool caseSensitive @true: Both upper & lower case letter must present to pass alphabet criteria. @false: Either upper or lower case letter present to pass alphabet criteria. Return value: void (None) @Ipang © 2017 SoloLearn Community */ #include #include // Special characters to check const std::string spchars {"@#*="}; // For counting whitespace const char wspc {' '}; void checkUserName( std::string inBuffer, bool verbose = false, bool caseSensitive = false) { if(inBuffer.empty()) return; size_t len {inBuffer.length()}; // This counts number of lowercase, // uppercase letters, numbers, the // special characters, and whitespace int lower {0}, upper {0}, digits {0}; int special {0}, spaces {0}; // Character type, returned by isalpha int cc {0}; for(char ch : inBuffer) { // isalpha function returns 0 if the // character is non alphabetical, // 1 for uppercase, 2 for lowercase cc = std::isalpha(ch); if(cc == 1) // Increment uppercase letter count upper++; else if(cc == 2) // Increment lowercase letter count lower++; else { if(std::isdigit(ch)) // Increment number count digits++; else { if(ch == wspc) // Increment whitespace count spaces++; // Increment special characters count if(spchars.find(ch) != std::string::npos) special++; } } } /* There should be at least a number, an uppercase and/or a lowercase letter (depending on caseSensitive), plus one of the special characters contained in the buffer before it can be classified as valid. The buffer should not contain any space to be considered valid also. Furthermore, a minimum of five characters and maximum of ten characters length is also considered. */ if(verbose) { std::cout << "User name:\n\t" << inBuffer << std::endl; std::cout << "\tUppercase letters: " << upper; std::cout << "\n\tLowercase letters: " << lower; std::cout << "\n\tNumbers: " << digits; std::cout << "\n\tSpecial characters: " << special; std::cout << "\n\tWhitespace: " << spaces; std::cout << "\n\tLength: " << len; std::cout << std::endl; } // Make decision here, should we care for // the alphabet letter case? bool pass = caseSensitive ? upper && lower : upper || lower; if(pass && digits && special && !spaces && (len >= 5 && len <= 10)) std::cout << "PASS\n"; else std::cout << "FAILED\n"; std::cout << std::endl; } // Main procedure int main() { std::string username; // Read on while not blank do { std::getline(std::cin, username); checkUserName(username, true); } while(!username.empty()); return 0; }

Challenge - Check username