palindrome.cpp

#include <iostream>
#include <string>
#include <cctype>
#include "Helpers.h"

using namespace std;

bool is_pal(const string& s);
string remove_punct(const string& s, const string& punct);
string reverse(const string& s);
void swap(char& v1, char& v2);

int main(){

	string input;

	cout << "Enter a string: ";
	getline(cin,input);

	if(is_pal(input))
		cout << "\"" << input + "\" is a palindrome.";
	else
		cout << "\"" << input + "\" is not a palindrome.";

	return 0;
}

bool is_pal(const string& s){
	string punct(",;:.'?\"!");
	string str(s);
	str = Helpers::strToLower(str);

	string lower_str = remove_punct(str,punct);

	return (lower_str == reverse(lower_str));
}
string remove_punct(const string& s, const string& punct){
	
	string no_punct;
	int strlen = s.length(),
	punctlen = punct.length();

	for(int i = 0; i< strlen; ++i){
		string a = s.substr(i,1);
		int loc = punct.find(a,0);

		if(loc < 0 || loc >= punctlen){
			no_punct = no_punct + a;
		}
	}

	return no_punct;

}
void swap(char& v1, char& v2){
	char temp = v1;
	v1 = v2;
	v2 = temp;
}
string reverse(const string& s){

	string temp = s;
	int start = 0,
		end = s.length();

	while (start < end){
		end--;
		swap(temp[start], temp[end]);
		start++;
	}

	return temp;

}