c++ - 具有堆栈和队列的字符串回文 (C++)

Question

这可以很好地编译并且在没有空格的情况下也能正常工作，但是一旦我在其中放入空格就会告诉我它不是回文或超时。任何帮助将不胜感激!

int main( )
{
   queue<char> q;
   stack<char> s;
   string the_string;
   int mismatches = 0;
   cout << "Enter a line and I will see if it's a palindrome:" << endl;
   cin  >> the_string;

   int i = 0;
   while (cin.peek() != '\n')
   {
       cin >> the_string[i];
       if (isalpha(the_string[i]))
       {
          q.push(toupper(the_string[i]));
          s.push(toupper(the_string[i]));
       }
       i++;
   }

   while ((!q.empty()) && (!s.empty()))
   {
      if (q.front() != s.top())
          ++mismatches;

        q.pop();
        s.pop();
   }

   if (mismatches == 0)
       cout << "This is a palindrome" << endl;
   else
       cout << "This is not a palindrome" << endl;

   system("pause");
   return EXIT_SUCCESS;
}

Answer 1

为什么这么复杂？

你可以简单地做:

#include <string>
#include <algorithm>

bool is_palindrome(std::string const& s)
{
  return std::equal(s.begin(), s.begin()+s.length()/2, s.rbegin());
}