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Code stuck in infinite loop

TomShoe (10)
Hello! I'm having an issue where I'm designing a palindrome checker. I have no problem with single words, but every time when I type in a phrase that has multiple words with spaces, my program loses its mind and goes into an infinite loop. Perhaps it has something to do with the loops I put inside? I've been step by step debugging with no success. Any help would be appreciated.

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  //Preprocessor directives
#include <iostream>
#include <cstdlib>
#include <string>
#include <iterator>
#include <vector>
#include <stdlib.h>

using namespace std;

//Function declarations
string input();
bool check(string a);

int main()
{
	//Repeater variable
	bool rep = 1;
	bool result = 0;

	//Declares string to be checked
	string palin;
	while (rep == 1)
	{
		//Creates string and calls input function
		palin = input();

		//Close function if stopped midway
		if (palin == "2")
		return 0;

		result = check(palin);

		//Displays the results
		if (result == 1)
			cout << palin << " is a palindrome." << endl;
		else
			cout << palin << " is not a palindrome." << endl;

		//Ask if the user wants to enter another Palindrome
		cout << "Continue? (1 for yes, 0 for no): ";
		cin >> rep;
	}

	cout << "Closing program..." << endl;
	system("pause");
	return 0;
}

string input()
{
	//Asks for and receives input string
	string temp;
	cout << "Please enter a string (type zero or 0 to quit): ";
	cin >> temp;

	//Close program if user enters 0 or zero
	if (temp == "0" || temp == "zero")
	{
		cout << "Exiting program..." << endl;
		system("pause");
		return "2";
	}

	//Check if string is null, then ask for input again
	if (temp.empty())
	{
		cout << "There is nothing entered. Please enter a string: ";
		cin >> temp;
	}

	//Check if string is too long, ask for input again
	if (temp.length() >= 80)
	{
		while (temp.length() > 80)
		{
			cout << "The string is too long. Please enter a smaller string: ";
			cin >> temp;
		}
	}
	return temp;
}

bool check(string a)
{
	//Creates 2 iterators that traverse the string
	string::iterator test1;
	string::reverse_iterator test2;

	test1 = a.begin();
	test2 = a.rbegin();

	//Continue until the end of either side of the string
	while (test1 != a.end() && test2 != a.rend())
	{
		//Check if the current symbol is alphanumeric
		while (test2 != a.rend() && !isalnum(*test2))
			++test2;
		while (test1 != a.end() && !isalnum(*test1))
			++test1;
		//Break loop when you hit the end
		if (test1 == a.end() || test2 == a.rend())
			break;
		//If they're not the same it's not a palindrome, exit function
		if (tolower(*test1) != tolower(*test2))
			return 0;

		++test1;
		++test2;
	}
	return 1;
}
TheIdeasMan (6817)
Hi,

std::cin only reads up to the first white space, that is one word. Consider using std::getline instead.

I've been step by step debugging with no success.


You should have seen that temp in the function input always contains one word.
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