//DISPLAY 8.8 Palindrome Testing Program
//Test for palindrome property.
#include <iostream>
#include <string>
#include <cctype>
using namespace std;

void swap(char& v1, char& v2);
//Interchanges the values of v1 and v2.

string reverse(const string& s);
//Returns a copy of s but with characters in reverse order.

string remove_punct(const string& s, const string& punct);
//Returns a copy of s with any occurrences of characters
//in the string punct removed.

string make_lower(const string& s);
//Returns a copy of s that has all uppercase
//characters changed to lowercase, other characters unchanged.

bool is_pal(const string& s);
//Returns true if s is a palindrome, false otherwise.

int main( )
{
    string str;
    cout << "Enter a candidate for palindrome test\n"
         << "followed by pressing Return.\n";
    getline(cin, str);

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

    return 0;
}

void swap(char& v1, char& v2)
{
    char temp = v1;
    v1 = v2;
    v2 = temp;
}
string reverse(const string& s)
{
    int start = 0;
    int end = s.length( );
    string temp(s);

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

    return temp;
}

//Uses <cctype> and <string>
string make_lower(const string& s)
{
    string temp(s);
    for (int i = 0; i < s.length( ); i++)
        temp[i] = tolower(s[i]);

    return temp;
}

string remove_punct(const string& s, const string& punct)
{
    string no_punct; //initialized to empty string
    int s_length = s.length( );
    int punct_length = punct.length( );

    for (int i = 0; i < s_length; i++)
    {
         string a_char = s.substr(i,1); //A one-character string
         int location = punct.find(a_char, 0);
         //Find location of successive characters
         //of src in punct.

      if (location < 0 || location >= punct_length)
         no_punct = no_punct + a_char; //a_char not in punct, so keep it
    }

    return no_punct;
}
//uses functions make_lower, remove_punct
bool is_pal(const string& s)
{
    string punct(",;:.?!'\" "); //includes a blank
    string str(s);
    str = make_lower(str);
    string lower_str = remove_punct(str, punct);

    return (lower_str == reverse(lower_str));
}