commit 5b03d9cea51aa874414cff76995d44079b172abe
Author: Sarnavskiy Alexey <alexey.sarnavskiy@ya.ru>
Date:   Sat Nov 27 23:54:28 2021 +0300

    Added main.cpp and Task_1..5.cpp

diff --git a/Task_1.cpp b/Task_1.cpp
new file mode 100644
index 0000000..ad321ad
--- /dev/null
+++ b/Task_1.cpp
@@ -0,0 +1,40 @@
+/*
+Выделить в памяти динамический одномерный массив типа int. Размер массива
+запросить у пользователя. Инициализировать его числами степенями двойки:
+1, 2, 4, 8, 16, 32, 64, 128 … Вывести массив на экран. Не забыть освободить
+память. =) Разбить программу на функции.
+*/
+
+#include <iostream>
+
+void PrintArray(int*, const size_t, std::string s = "");
+void FillArrayByTwoPowers(int*, const size_t);
+
+int Task_1()
+{
+	std::cout << "\t\tTask #1" << std::endl;
+	size_t n = 0;
+	std::cout << "Enter array size: ";
+	std::cin >> n;
+	int* aInts = new (std::nothrow) int[n];
+
+	if (aInts != nullptr && n > 0)
+	{
+		std::cout << "Memory allocation is successful." << std::endl;
+		FillArrayByTwoPowers(aInts, n);
+		PrintArray(aInts, n);
+	}
+	else
+	{
+		std::cerr << "Something wrong with memory allocation in Task #1.\n";
+		return -1;
+	}
+
+	std::cout << "Allocated memory deletion ...\n";
+	delete[] aInts;
+
+	std::cout << "________________________________________________\n\n";
+	system("pause");
+	system("cls");
+	return 0;
+}
diff --git a/Task_2.cpp b/Task_2.cpp
new file mode 100644
index 0000000..d518114
--- /dev/null
+++ b/Task_2.cpp
@@ -0,0 +1,50 @@
+/*
+Динамически выделить матрицу 4х4 типа int. Инициализировать ее псевдослучайными
+числами через функцию rand. Вывести на экран. Разбейте вашу программу на
+функции которые вызываются из main.
+*/
+
+#include <iostream>
+
+void PrintArray(int**, const size_t);
+void FillRandArray(int**, const size_t);
+
+int Task_2()
+{
+	std::cout << "\t\tTask #2" << std::endl;
+
+	const size_t SIZE = 4U;
+	int** aaInts = new (std::nothrow) int* [SIZE];
+	if (aaInts != nullptr && SIZE > 0)
+	{
+		for (size_t i = 0; i < SIZE; i++)
+		{
+			aaInts[i] = new int[SIZE];
+			if (aaInts[i] == nullptr)
+			{
+				std::cerr << "Something wrong with memory allocation in Task #2.\n";
+				return -1;
+			}
+		}
+		std::cout << "Memory allocation is successful." << std::endl;
+		FillRandArray(aaInts, SIZE);
+		PrintArray(aaInts, SIZE);
+	}
+	else
+	{
+		std::cerr << "Something wrong with memory allocation in Task #2.\n";
+		return -1;
+	}
+
+	std::cout << "Allocated memory deletion ...\n";
+	for (size_t i = 0; i < SIZE; i++)
+	{
+		delete[] aaInts[i];
+	}
+	delete[] aaInts;
+
+	std::cout << "________________________________________________\n\n";
+	system("pause");
+	system("cls");
+	return 0;
+}
diff --git a/Task_3.cpp b/Task_3.cpp
new file mode 100644
index 0000000..826e934
--- /dev/null
+++ b/Task_3.cpp
@@ -0,0 +1,39 @@
+/*
+Написать программу, которая создаст два текстовых файла (*.txt), примерно
+по 50-100 символов в каждом (особого значения не имеет с каким именно содержимым).
+Имена файлов запросить у польлзователя.
+*/
+
+#include <iostream>
+
+int FillFileBySmth(std::string);
+
+int Task_3()
+{
+	std::cout << "\t\tTask #3" << std::endl;
+
+	std::string filename_1;
+	std::string filename_2;
+	int result = 0;
+
+	std::cout << "Enter name of the 1st text file without extension:\n";
+	std::cin >> filename_1;
+	std::cout << "Enter name of the 2nd text file without extension:\n";
+	std::cin >> filename_2;
+
+	filename_1 += ".txt";
+	filename_2 += ".txt";
+
+	result = FillFileBySmth(filename_1);
+	if (result != 0)
+	{
+		std::cerr << "Something wrong with file creation in Task #3." << std::endl;
+		return result;
+	}
+	result = FillFileBySmth(filename_2);
+
+	std::cout << "________________________________________________\n\n";
+	system("pause");
+	system("cls");
+	return result;
+}
diff --git a/Task_4.cpp b/Task_4.cpp
new file mode 100644
index 0000000..b62dc87
--- /dev/null
+++ b/Task_4.cpp
@@ -0,0 +1,41 @@
+/*
+* Написать функцию, «склеивающую» эти файлы в третий текстовый файл (имя файлов
+спросить у пользователя).
+*/
+
+#include <iostream>
+
+int GlueTwoFilesInThird(std::string, std::string, std::string);
+
+int Task_4()
+{
+	std::cout << "\t\tTask #4" << std::endl;
+
+	int result = 0;
+	std::string filename_1;
+	std::string filename_2;
+	std::string filename_3;
+
+	std::cout << "Enter name of the 1st file without extension:\n";
+	std::cin >> filename_1;
+	std::cout << "Enter name of the 2nd file without extension:\n";
+	std::cin >> filename_2;
+	std::cout << "Enter name of the 3rd glued file without extension:\n";
+	std::cin >> filename_3;
+
+	filename_1 += ".txt";
+	filename_2 += ".txt";
+	filename_3 += ".txt";
+
+	result = GlueTwoFilesInThird(filename_1, filename_2, filename_3);
+	if (result != 0)
+	{
+		std::cerr << "Files not found or not created.\n";
+		return result;
+	}
+
+	std::cout << "________________________________________________\n\n";
+	system("pause");
+	system("cls");
+	return result;
+}
diff --git a/Task_5.cpp b/Task_5.cpp
new file mode 100644
index 0000000..cc902cd
--- /dev/null
+++ b/Task_5.cpp
@@ -0,0 +1,61 @@
+/*
+* Написать программу, которая проверяет присутствует ли указанное пользователем
+при запуске программы слово в указанном пользователем файле (для простоты работаем
+только с латиницей). Используем функцию find которая есть в строках std::string.
+*/
+
+#include <iostream>
+#include <fstream>
+
+const unsigned int MAX_SENTENTECE_SIZE = 100U;
+
+int Task_5()
+{
+	std::cout << "\t\tTask #5" << std::endl;
+	
+	int result = 0;
+	std::string filename = "";
+	std::string word_to_find = "";
+	std::string s1 = "";
+
+	std::cout << "Enter file name where you want to find your word (without extension):\n";
+	std::cin >> filename;
+	filename += ".txt";
+
+	std::ifstream in_file(filename);
+	if (!in_file)
+	{
+		std::cerr << "File is not open! Check file existance!\n";
+		return -3;
+	}
+
+	std::cout << "Enter the word to find in this file: ";
+	std::cin >> word_to_find;
+	bool word_is_found = false;
+	
+	while (!in_file.eof() || word_is_found != false)
+	{
+		char tmp[MAX_SENTENTECE_SIZE + 1] = {};
+		in_file.getline(tmp, MAX_SENTENTECE_SIZE, ' ');
+		s1 += tmp;
+		s1 += ' ';
+	}
+	if (s1.find(word_to_find) != std::string::npos)
+	{
+		word_is_found = true;
+	}
+
+	if (word_is_found)
+	{
+		std::cout << "Word was found!\n";
+	}
+	else
+	{
+		std::cout << "Word was not found!\n";
+	}
+
+	std::cout << "________________________________________________\n\n";
+	system("pause");
+	system("cls");
+	return result;
+}
\ No newline at end of file
diff --git a/main.cpp b/main.cpp
new file mode 100644
index 0000000..d0199ab
--- /dev/null
+++ b/main.cpp
@@ -0,0 +1,149 @@
+п»ї#include <iostream>
+#include <fstream>
+#include <string>
+
+const unsigned int MAX_SENTENTECE_SIZE = 100U;
+
+int Task_1();
+int Task_2();
+int Task_3();
+int Task_4();
+int Task_5();
+
+int main()
+{
+	int result = 0;
+
+	result = Task_1();
+	if (result != 0)
+	{
+		return result;
+	}
+	result = Task_2();
+	if (result != 0)
+	{
+		return result;
+	}
+	result = Task_3();
+	if (result != 0)
+	{
+		return result;
+	}
+	result = Task_4();
+	if (result != 0)
+	{
+		return result;
+	}
+	result = Task_5();
+	if (result != 0)
+	{
+		return result;
+	}
+
+	return result;
+}
+
+void PrintArray(int* pArr, const size_t count, std::string s)
+{
+	std::cout << s;
+	for (size_t i = 0U; i < count; i++)
+	{
+		std::cout << "Array[" << i << "] = " << pArr[i] << std::endl;
+	}
+}
+
+void PrintArray(int** pArr, const size_t count)
+{
+	for (size_t i = 0U; i < count; i++)
+	{
+		for (size_t j = 0U; j < count; j++)
+		{
+			std::cout << "\t" << pArr[i][j];
+		}
+		std::cout << std::endl;
+	}
+}
+
+void FillArrayByTwoPowers(int* pArr, const size_t count)
+{
+	pArr[0U] = 1;
+	for (size_t i = 1U; i < count; i++)
+	{
+		pArr[i] = pArr[i - 1U] << 1;
+	}
+}
+
+void FillRandArray(int** ppArr, const size_t count)
+{
+	for (size_t i = 0U; i < count; i++)
+	{
+		for (size_t j = 0U; j < count; j++)
+		{
+			ppArr[i][j] = rand();
+		}
+	}
+}
+
+int FillFileBySmth(std::string filename)
+{
+	std::string s = "This is a small text with little quantity of symbols created in Microsoft Visual Studio.\n";
+	std::ofstream outfile(filename);
+
+	if (!outfile)
+	{
+		return -2;
+	}
+	
+	std::cout << "File \"" << filename << "\" is open successfully.\n";
+
+	outfile << s;
+
+	outfile.close();
+	return 0;
+}
+
+int GlueTwoFilesInThird(std::string filename_1, std::string filename_2, std::string outfilename)
+{
+	std::string s1 = "";
+	std::string s2 = "";
+	std::ifstream in_file_1(filename_1);
+	std::ifstream in_file_2(filename_2);
+
+	if (!in_file_1 || !in_file_2)
+	{
+		return -2;
+	}
+	std::cout << "Files \"" << filename_1 << "\" and \"" << filename_2 << "\" are succesfully open.\n";
+	
+	while (!in_file_1.eof())
+	{
+		char tmp[MAX_SENTENTECE_SIZE + 1] = {};
+		in_file_1.getline(tmp, MAX_SENTENTECE_SIZE, '\n');
+		s1 += tmp;
+		s1 += "\n";
+	}
+	while (!in_file_2.eof())
+	{
+		char tmp[MAX_SENTENTECE_SIZE + 1] = {};
+		in_file_2.getline(tmp, MAX_SENTENTECE_SIZE, '\n');
+		s2 += tmp;
+		s2 += "\n";
+	}
+
+	in_file_1.close();
+	in_file_2.close();
+	std::cout << "Files \"" << filename_1 << "\" and \"" << filename_2 << "\" are closed.\n";
+
+	std::ofstream out_file(outfilename);
+	if (!out_file)
+	{
+		return -2;
+	}
+	std::cout << "File \"" << outfilename << "\" is successfully open.\n";
+
+	out_file << s1 + s2;
+	out_file.close();
+	std::cout << "File \"" << outfilename << "\" is closed.\n";
+
+	return 0;
+}