algorithm - having a difficulty with making a palindrome program c++ -

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• std::cin input spaces? 8 answers

hi code palindrome program:

void palindrome() {     string input;     bool checkinput, palindrome;     palindrome = true;         {         checkinput = false;         cout << "enter word, phrase or sentence :\n";         getline(cin, input);          (unsigned int = 0; < input.size(); i++)         {             if (input[i] < 65 || input[i] > 90 && input[i] < 97 || input[i] > 122)             {                 checkinput = true;             }         }        } while (checkinput);      (unsigned int = 0, j = input.size() - 1; < input.size(); i++, j--)     {         if (input[i] != input[j] && input[i] + 32 != input[j] && input[i] - 32 != input[j])         {             palindrome = false;             break;         }     }      if (palindrome)     {         cout << "\n\nto consider letters , digits:\n";         cout << input << "\nyes, palindrome!\n";         cout << "\t\t press <enter> key menu";         fflush(stdin);         cin.get();     }     else     {         cout << "\n\nto consider letters , digits:\n";         cout << input << "\nnope, it's not palindrome\n";         cout << "\t\t press <enter> key menu";         fflush(stdin);         cin.get();     } } 

and when input racecar reads , says palindrome, when input race car (with space) doesn't read , says not palindrome. intend ignore spaces. appreciated! in advance!

**editted switched cin >> input getline(cin, input) , doesnt let me input words or phrases

the problem

the palindrome word spelled backwards , forwards same. therefore, can sure that, going outside in, letters need same until you're examining same letter (the total number of letters odd) or letter-searching things/examiners/markers (let's call them iterators) criss-cross.

how examine pair of letters outside inside? using index loop first last position in tandem last-to-first index loop.

how (the implementation)

let's pretend have 2 variables act iterators, , j. move forward while j move backward. start @ opposite ends:

#include <iostream> #include <string> #include <algorithm>  int main() {     //this our word be.     std::string str;      //get input     std::cout << "input word, please!" << std::endl;     std::getline(std::cin, str);      //let's use std::erase take away our whitespaces     //c++11 library <algorithm>     str.erase(remove_if(str.begin(), str.end(), isspace), str.end());      //initialize , j, our iterators     //i use auto because iterator type long. it's reason why auto invented.     auto = str.begin();     auto j = str.end() - 1;     //you see, str.end() end, , not last letter.     //that's why has -1.      bool is_palindrome = true;      while (i < j) //while 2 haven't crossed yet     {         //this std::cout shows , j @ each repeat         std::cout << "i = " << *i << " ||| j = " << *j << std::endl;          //if 2 characters marked 2 iterators not equal         if (*i != *j)         {             is_palindrome = false;             break;         }         else         {             //let's continue.             ++i;             --j;         }     }      //if loop gets point successfully, it's palindrome.     if (is_palindrome)         std::cout << str << " palindrome!" << std::endl;     else         std::cout << str << " not palindrome." << std::endl;      return 0; } 

hopefully you. remember compile -std=c++11 c++11 features!