You'll write a C++ program to demonstrate thread synchronization. Your main function should first create an empty file called *sync.txt*. Then it will create two separate threads: *Thread-A* and *Thread-B*. Both threads will open *sync.txt* and write to it simultaneously.   *Thread-A* will write the numbers 0 through 9, a total of fifty-thousand times in nested `for` loops, then exit. In other words, print the numbers 0 through 9 over and over again, with each run on a separate line, for 50,000 lines. Here's an example of one such line: ```text 0 1 2 3 4 5 6 7 8 9 ```   Somewhat similarly, *Thread-B* will write the letters A through Z fifty-thousand times in nested `for` loops, then exit. In other words, print the letters A through Z over and over again, with each run on a separate line, for 50,000 lines. Here's an example of one such line:   ```text A B C D E F G H I J K L M N O P Q R S T U V W X Y Z ```   Do not write each line as one long string. You must write each character to the file, one by one (i.e., using multiple calls ). After writing a character to the file, write a space too, so the characters appear visually separated.   This means each thread would use a doubly-nested `for` loop. The outer loop would run 50,000 times (once per line), and the inner loop would run either 26 times (once per character) or 10 times (once per digit).   Hopefully, you understand this might create a race condition. Because *Thread-A* and *Thread-B* will both attempt to write individual characters to the same file at the same time, we might expect to see an undesirable mixing of the two types of lines, rather than each line remaining intact.   ## Solving With a Critical Section   We'll solve the previous dilemma with a *critical section* in our code. You will use a mutex lock to control synchronization between the two threads, such that each line of numbers or letters will render uninterrupted, even with multiple competing writes to the file. 1. We ***don't*** want to mix letters and numbers on a single line. Each line should only contain letters *or* numbers, but not both.   2. We ***do*** want line types to change sometimes. In other words, you might see a line of letters followed by a line of numbers. Or you may later see a line of numbers followed by a line of letters. You wouldn't want to see 100 lines of letters followed by 100 lines of numbers.   Try to make your *critical section* as small as possible while still solving the race condition for the above criteria.   ### Overview of beginWriting()   You'll quickly see the following prototype in your starter code:   ```cpp void beginWriting(bool use_mutexes); ```   At minimum, this function should perform the following steps:   1. Take the incoming argument `use_mutexes` and assign its value to the global variable `G_USE_MUTEXES`.   2. Create both threads.   3. Join both threads.   ### Overview of Thread Runner Functions   You will also see two prototypes for your thread runner functions:   ```cpp void* threadAEntry(void* param); void* threadBEntry(void* param); `` 1. Each individual line contains only letters *OR* numbers, but not both. 2. There should not be 100 lines of one type, followed by 100 lines of another type. Some lines should be of a different type than the last.   Here's an shortened example of what a successfully written file might look like (although yours may be slightly different):   ```text 0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 ```   ## Confirming Failure   As stated above, no line should have a mix of letters *and* numbers. Here is an example that shows your *critical section* isn't working, or perhaps needs to cover a larger area:   ```text A 0 1 B C 2 3 4 D E 5 F 6 7 G 8 H 9 I J K L M N O P Q R S T U V W X Y Z ```   Also, you should not see a block of 50,000 lines of any particular type in a row. We expect to see the lines switch up a bit. Here's the general idea (some lines omitted and parenthetical added for explanation), which may indicate your *critical section* covers *too much* code.   ```text A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A B C D E F G H I J K L M N O P Q R S T U V W X Y Z (letter lines repeat a total of 50,000 times) 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 (number lines repeat a total of 50,000 times) ```

in C++ answer the following question in the image :

need code for this in python or java thanks

In UNIX, how would you remove the directory test and all files and subdirectories (recursively) in it? The directory test is located in (is a subdirectory of) /home/myid/smith/projects. O rmdir /home/myid/smith/projects/test O rmdir -r /home/myid/smith/projects/test rm -r /home/myid/smith/projects/test O rm -r projects/test

Need help to implement networking in python Server.py Load data from file This option will ask the user for a fully qualified path and will load a JSON file containing the information for users and pending messages. The format of the JSON file will be defined based on your implementation and it will the same used to save the data into file (menu option #4). Functionalities the server must provide: 1) User Sign Up: adds a user identified by a phone number to the system. a) Protocol: USR|username|password|display_name b) Response: 0|OK for success. 1| for an error. c) The server should validate that the username does not exist 2) User Sign In: verify user credentials a) Protocol: LOG|username|password b) Response: i) 0|OK → the credentials are correct. ii) 1|Invalid Credentials iii) 2|Already Logged In → in case that the user is logged in from another client. c) This will help the server knowing which user is connected. d) The server should keep a list of connected clients, which should…

Implement a simple version of the linux grep command in C++. grep - Looks through a file, line by line, trying to find a user-specified search term in the line. If a line has the word within it, the line is printed out, otherwise it is not. Use the system calls open(), getline(), close().  Requirements (examples run from. terminal) Your program grep is always passed a search term and zero or more files to grep through (thus, more than one is possible). It should go through each line and see if the search term is in it; if so, the line should be printed, and if not, the line should be skipped. [terminal]$ ./grep ! main.cpp main2.cppcout << "Hello, World!";cout << "Programming is great fun!"; The matching is case sensitive. Thus, if searching for world, lines with World will not match.  Lines can be arbitrarily long (that is, you may see many many characters before you encounter a newline character, \n). grep should work as expected even with very long lines. For this,…