/* ----------------------------------------------------------- Convert an integer into a string then reverses the string. ----------------------------------------------------------- Instructions: Enter an integer to be converted into a string data type and reversed. Try Entering a number that ends in a zero (0) +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ */ // How it works.. #include // #include // provides access to cin / cout #include //#include // provides access to string #include //#include // ostringstream #include // provides access to reverse using namespace std; // includes entire std namespace. allows us to reference things without qualification. ie. cout vs std::cout and cin vs std::cout // caveat: You can create things with conflicting names if you make the entire namespace available. So just be sure to be creative and not namethings the same as functions that would be obviously available and you should be ok. int main() { unsigned int myNumber; // declare a new iteger. // This int type can only store whole numbers. // The int data type is fine for our needs. // Note: We have used the unsigned modifier on int because we won't be dealing with negative numbers here. string numberString; // declare a new string numberString. This is where we will store the converted number. Anything stored here we actually be a char array. made up of characters. unsigned int ReversedNumber; cin >> myNumber; // prompt the user to enter a number if(!std::cin) { // if the data entered by the user is not of the correct type. Tell them. and the program will end. cout << "Enter a number next time please"; // clear the cin buffer and ignore any errors before we go. std::cin.clear(); std::cin.ignore(); } else { /* The user must of entered a number. Now we can get to work. */ ostringstream convert; /* Create an output stream class to operate on strings. we will call it convert as that is what we will be using it for. (converting an int to a string) For more information on ostringstream see: http://www.cplusplus.com/reference/sstream/ostringstream/ */ convert << myNumber; // put myNumber as int into convert the stringstream. this converts the number into a series of characters numberString = convert.str(); // put the stringstreams characters into a string. Remembering that the sequence of characters held in convert can be accessed directly as a string object by using the member str. reverse(numberString.begin(), numberString.end()); // reverse the string by using the reverse funtion found in the algorithm header // see: http://www.cplusplus.com/reference/algorithm/reverse/ //convert reversed number back to an integer using istringstream this time istringstream convertBack(numberString); // see http://www.cplusplus.com/reference/sstream/istringstream/ convertBack >> ReversedNumber; cout << "Reversed as String: " << numberString << "\n"; //output the string to the screen cout << "Reversed as Integer: " << ReversedNumber << "\n"; //output the integer to the screen } // end the program gracefully. return 0; }

Convert Integer to string and Reverse