How do you print only part of a string?

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I need help with the following lab. Can anyone explain it to me on how to approach this problem. Coding would be great too !!! No busy waiting allowed. Remember that Java monitors are 'signal and continue'. The input data is called the database (DB). In this problem, it consists of a single variable initialized in the main thread, to contain the current time of day in HH:MM:SS:mmm format (mmm is milliseconds) truncated to 3 digits. Threads follow these rules: 1. Readers may all attempt to read at the same time, but NOT if a writer is writing (i.e.; the writer is in the monitor. 2. Writing is exclusive (only 1 writer at a time, no readers while writing). 3. Options: (to be specified by instructor) a. Readers have absolute priority over writers. b. Writers have absolute priority over readers c. When a reader arrives and a writer is waiting, the reader is suspended behind the writer instead of being admitted immediately. Thus, a writer waits for readers that were running when it arrived, but does not to wait for new readers. You may program this in C++ or Java. There are 4 controlling input values: 1. r – number of readers 2. w – number of writers 3. R – delay for a reader to restart 4. W – delay for a writer to restart Create the following program consisting of 1 main process (your main program) with n threads: 1. The main thread: a. Creates the 'n' threads needed. Of these, r of them are readers and w of them are writers. Starts all readers and writers. b. Waits for all 'n' threads to complete. You may use any method to detect when they are all complete. c. Prints out the resulting outputs from the threads. 2. Threads: a. When a thread starts to run, it immediately tries to enter the monitor. b. A reader thread reads the DB, outputs the exact message below, then exits: >>> DB value read =: HH:MM:SS:mmm by reader number: rr where the underlined text is replaced with actual data. c. A writer thread updates the DB with a new value (from the system time), outputs the exact message below, then exits: *** DB value set to: HH:MM:SS:mmm by writer number: ww where the underlined text is replaced with actual data. d. Each thread accesses the data a total of 10 times, exiting, then re-entering the monitor after each access. Hints: 1. File access *might* not be thread-safe, so you should be prepared to handle this. Read the documentation for the language you are using. 2. Suggested values for delays are: a. If looping, R >=1,000,000 and W>=100,000 b. If using “sleep”, then R=100 ms, W=50 ms. Additional: • Thread output is to ONE file used by ALL threads (so you need to synchronize access to it). • Readers must provide sufficient delay that results are useful (delay by R before re-trying). R is another input value. • Writers must also delay. Delay by W, updating the DB each time. W is an input. • Test your program with AT LEAST TWO different sets of values for r and w (#s of readers and writers) plus this set: r = 4, w=2. Basic operation of a thread: attempt to enter the monitor. If unsuccessful, you get put on a queue. When you get in, read or write the data (depending on type of thread), exit the monitor, wait the required delay amount, then try again. Repeat 10 times.

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in ‘C’ language for Matrix Multiplication fails” Introspect the causes for its failure and write down the possible reasons for its failure.

7993

What is static and auto variables in c?

1023

What are the restrictions of a modulus operator?

1066

Is return a keyword in c?

1032

What is the difference between c &c++?

1091

What is the -> in c?

957

how we can make 3d venturing graphics on outer interface

4734

What is dynamic memory allocation?

1287

How pointer is different from array?

1020

Can you write the function prototype, definition and mention the other requirements.

1086

What is derived datatype in c?

1040

What is actual argument?

1005

I need testPalindrome and removeSpace #include #define SIZE 256 /* function prototype */ /* test if the chars in the range of [left, right] of array is a palindrome */ int testPalindrome( char array[], int left, int right ); /* remove the space in the src array and copy it over to the "copy" array */ /* set the number of chars in the "copy" array to the location that cnt points t */ void removeSpace(char src[], char copy[], int *cnt); int main( void ) { char c; /* temporarily holds keyboard input */ char string[ SIZE ]; /* original string */ char copy[ SIZE ]; /* copy of string without spaces */ int count = 0; /* length of string */ int copyCount; /* length of copy */ printf( "Enter a sentence:\n" ); /* get sentence to test from user */ while ( ( c = getchar() ) != '\n' && count < SIZE ) { string[ count++ ] = c; } /* end while */ string[ count ] = '\0'; /* terminate string */ /* make a copy of string without spaces */ removeSpace(string, copy, ©Count); /* print whether or not the sentence is a palindrome */ if ( testPalindrome( copy, 0, copyCount - 1 ) ) { printf( "\"%s\" is a palindrome\n", string ); } /* end if */ else { printf( "\"%s\" is not a palindrome\n", string ); } /* end else */ return 0; /* indicate successful termination */ } /* end main */ void removeSpace(char src[], char copy[], int *cnt) { } int testPalindrome( char array[], int left, int right ) { }

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