Write a cpp program to convert entered date into words?

Answer 1

#include<iostream>

#include<sstream>

#include<chrono>

#include<ctime>

std::string months[12] { "January", "February", "March", "April", "May", "June", "July",

"August", "September", "October", "November", "December"};

class date

{

public:

date (std::string = "");

date (size_t dd, size_t mm, size_t yyyy);

date (const date& dt): d{dt.d}, m{dt.m}, y{dt.y} {}

date (date&& dt): d{dt.d}, m{dt.m}, y{dt.y} {}

date& operator= (const date& dt) { d = {dt.d}, m = {dt.m}, y = {dt.y}; return *this; }

date& operator= (date&& dt) { d = {dt.d}, m = {dt.m}, y = {dt.y}; return *this; }

static bool is_leap_year (size_t year);

static date today ();

static bool validate (size_t dd, size_t mm, size_t& yyyy);

size_t day() const { return d; }

size_t month() const { return m; }

size_t year() const { return y; }

operator std::string () const;

private:

size_t d;

size_t m;

size_t y;

};

bool date::is_leap_year (size_t year)

{

if (!(year%4)) return false;

if (!(year%100)) return true;

if (!(year%400)) return false;

return true;

}

date date::today()

{

time_t tt = time (nullptr);

struct tm *tm = localtime (&tt);

return date (tm->tm_mday, tm->tm_mon+1, tm->tm_year+1900);

}

bool date::validate (size_t dd, size_t mm, size_t& yyyy)

{

// There was no year zero!

if (!yyyy)

return false;

// There is no day zero!

if (!dd)

return false;

// Check day and month combinations.

switch (mm)

{

case 2:

if (dd > 29 (dd > 28 && !date::is_leap_year (yyyy)))

return false;

break;

case 1: case 3: case 5: case 7: case 8: case 10: case 12:

if (dd > 31)

return false;

break;

case 4: case 6: case 9: case 11:

if (dd > 30)

return false;

break;

default:

return false;

}

// 10 dates were skipped during the switch from Julian to Gregorian

if (yyyy==1582 && mm==10 && dd>4 && dd<15)

return false;

// The date is valid!

return true;

}

date::date (size_t dd, size_t mm, size_t yyyy): d {dd}, m {mm}, y {yyyy}

{

if (!validate (dd, mm, yyyy))

throw std::range_error ("date (size_t,size_t,size_t) - invalid date values!");

}

date::date (std::string ddmmyyyy)

{

if (!ddmmyyyy.size())

{

date dd (today());

d = dd.d;

m = dd.m;

y = dd.y;

return;

}

const std::string error {"date(std::string) - invalid argument!"};

const std::string valid {"0123456789\"};

// check for invalid characters

if (ddmmyyyy.find_first_not_of (valid) != ddmmyyyy.npos)

throw std::range_error (error);

// locate first slash

size_t s1 = ddmmyyyy.find('\\');

if (!s1 s1 ddmmyyyy.npos)

throw std::range_error (error);

// ensure no more slashes

size_t s3 = ddmmyyyy.find ('\\', s2+1);

if (s3 != ddmmyyyy.npos)

throw std::range_error (error);

// parse string

std::string sd = ddmmyyyy.substr (0, s1);

std::string sm = ddmmyyyy.substr (s1+1, s2-s1-1);

std::string sy = ddmmyyyy.substr (s2+1, ddmmyyyy.size()-s2);

std::stringstream ss;

ss << sd << " " << sm << " " << sy;

size_t dd, mm, yyyy;

ss >> dd;

ss >> mm;

ss >> yyyy;

if (!validate(dd,mm,yyyy))

throw std::range_error (error);

d = dd;

m = mm;

y = yyyy;

}

date::operator std::string () const

{

std::stringstream ss;

ss << d << '\\' << m << '\\' << y;

return ss.str();

}

int main()

{

date d;

std::string input;

while (true)

{

std::cout << "Enter a date (dd\\mm\\yyyy): ";

std::cin >> input;

try

{

date t {input};

d = t;

break;

}

catch (std::range_error& e)

{

std::cerr << e.what() << std::endl;

}

}

std::cout << "Date: " << d.day();

switch (d.day() % 10)

{

case (1): std::cout << "st"; break;

case (2): std::cout << "nd"; break;

case (3): std::cout << "rd"; break;

default: std::cout << "th"; break;

}

std::cout << " " << months[d.month()-1] << ", " << d.year() << std::endl;

}