Lab 01

lab1.cpp

#include <iostream>
#include <string>
#include "riostream.h"
#include <sstream>

using namespace std;

// returns <number> plural form from (<one>,<few>,<many>)
string pluralNumber(int number, string one, string few, string many)
{
	// modulo - last digit of number
	int modulo = number % 10;

	// one
	if (number == 1 || modulo == 1)
		return one;
	
	// number∈(1;5) or n∈(20;+inf) and modulo∈(1;5) - few
	if ((number > 1 && number < 5) || (number > 20 && modulo > 1 && modulo < 5))
		return few;
	
	//else - many
	return many;
}

// returns time of the day, depending on the <hours>
string getDayTime(int hours)
{
	string daytime;

	if (hours > 12)
	{
		// pm
		hours -= 12; 
		if (hours < 6)
			daytime = " дня";
		else
			daytime = " вечера";
	}
	else 
	{
		// am
		if (hours < 6)
			daytime = " ночи";
		else
			daytime = " утра";

		if (hours == 12)
			daytime = " дня";

		if (hours == 0)
			hours = 12;
	}

	return daytime;
}

// checks format (hh:mm) and range (h∈[0;24), m∈[0;60)) of time in <s>
// if correct - returs 1, else - 0
bool isCorrectTime(string s)
{
	// format
	if (s.length()!=5)
		return false;

	if ( !( s[2] == ':' 
		&& isdigit(s[0]) 
		&& isdigit(s[1]) 
		&& isdigit(s[3]) && isdigit(s[4]) ) )
		return false;
	
	// parse minutes and hours
	int h = atoi(s.substr(0,2).c_str()); // hours
	int m = atoi(s.substr(3,5).c_str()); // minutes

	// check range (h∈[0;24), m∈[0;60))
	if ((h >= 0) && (m >= 0) && (h < 24) && (m < 60))
		return true;
	else
		return false;
}

// returns time <s> in verbal form
// format: hh:mm
string parseToVerbalTime(string s)
{
	stringstream stream;
	string h = s.substr(0,2);
	string m = s.substr(3,5);

	int hours = atoi(h.c_str());
	int minutes = atoi(m.c_str());

	string daytime = getDayTime(hours); 

	// check for midnight or 12:00
	if (minutes == 00)
		if (hours == 12)
			return "полдень";
		else if (hours == 00)
			return "полночь";

	if (hours > 12)
		hours-=12;

	stream << hours; // convert int => string
	h = stream.str();

	stream.clear(); stream.str(""); // reset stream
	stream << minutes; // convert int => string
	m = stream.str();

	return h + " " + pluralNumber(hours, "час", "часа", "часов") + " " 
		+ m + " " + pluralNumber(minutes, "минута", "минуты", "минут") + " " + daytime;
}

int main()
{
		string input;
		cout << "Введите время в формате чч:мм" << endl;
		while (1)
		{
			cin >> input;
			if (isCorrectTime(input))
				break; // continue to process the correct user input
			else
				cout << "Время введено неверно, попробуйте еще раз" << endl;
		}
		cout << "Время: " << parseToVerbalTime(input) << endl;
		system("pause");
		return 0;
}