////////////////////////////////////////////////////////////////////// //////////**************CHALLENGE:Anadrome string (solution with class Anad) //////////****************Author: Petros Simidyan ////////***************** //Idea: if the all letter of a given string occour even times, // or only one letter occours odd times, then the input string is //anadrome. For example: aann is anadrome (only "even occouring"), //"zanna" is anadrome too, because only one letter (in this case 'z') // occours odd times, but "zeanna" is not a anadrome string //(as well 'z' as 'e'occours odd times). So we need to test that #include //3 inline function to "prepare" the give string //the functions help to read only letters ffrom input //string and convert it in upper case inline const bool& isLetter(const char& c) { return (c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z'); } inline const bool& isLow(const char& c) { return (c >= 'a' && c <= 'z'); } inline const char& toUp(const char& c) { if (isLow(c)) return (c - 'a' + 'A'); else return c; } //function returns the number of the letter in alphabet (e.g. A=0, D=3) inline const int& indOf(const char& c) { return (int)(c - 'A'); } inline const bool& isOdd(const int& i) { return i & 1; } const int alphSize = 26; const int max = 256; class Anad { //an array of the short value which //saves the number of occourance //of each letter of the input string short alpha[alphSize]; char text[max]; public: Anad(const char* input = "") { initText(input); for (int k = 0; k < alphSize; k++) alpha[k] = 0; } //class method to prepare the given input in suitable form //for future testing and save it in class variable text void initText(const char* input) { int i = 0, j = i; while (input[i] != '\0'&&i < max) { if (isLetter(input[i])) text[j++] = toUp(input[i]); ++i; } text[j] = '\0'; } const bool& isAnad() { //bool variable returns "true", if //one of the letters in given string //occours odd times int i = 0; bool oneIsOdd = false; while (text[i] != '\0') ++alpha[indOf(text[i++])]; i = 0; while (i < alphSize) { if (isOdd(alpha[i++])) if (oneIsOdd) return false; else oneIsOdd = true; } return true; } }; int main() { Anad a1("zanna"), a2("anna"), a3("zaanna"); std::cout << a1.isAnad() << std::endl; std::cout << a2.isAnad() << std::endl; std::cout << a3.isAnad() << std::endl; return 0; }

CHACHALLENGE:Anadrome string (solution using class Anad)