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For the output string: 11001100…….

We have to take,

For process P:

W = P(T)

X = V (S)

For process q:

Y = P(S)

Z = V (T), where, S = 1 and T = 0

So, in this when we try to execute process P, it will go to P(T) as T = 0, it cannot enter into critical section.

So, we try to execute process Q.

It will go to P(S), As S = 1, so process q will enter into critical section and make S = 0 and print 11, then after its exit from critical section only, we can execute process P and print 00.

So, both process P and Q depends on each other to enter the critical section. In this way, it prints the sequence 11001100……

Concept:

Fork system call is used to create a new process also called as child processes.

Formula:

With n fork system calls, number of child processes created are 2ⁿ – 1.

Printf statement will be executed 2ⁿ times with n system calls.

Explanation:

Here there are 3 fork system calls in the given program.

So, 2³ times printf statement will be executed.

i.e. 8 times “child process created” will be printed.

Answer: Option 1

Explanation: 

We have given a cache memory organization with m lines in which the cache is divided into v sets, each of which consists of k lines.

Consider m = 8, v = 4, k = 2

Representation for this organization is:

To reduce it to direct mapping:

Make v = m, because in both direct mapping and set associative mapping, we have to take the mod operation to find the line number and set number respectively.

Also, make k = 1, because each set starts behaving like a line as in the case of direct mapping.

An undirected graph is called biconnected if there are two vertex – disjoint paths between any two vertices. A biconnected graph is connected and non-separable graph means, there is no vertex in the graph whose removal disconnects the graph.

Example:

This graph doesn’t have any vertex whose removal disconnects this graph.

When we declare a variable as unsigned, it doesn’t mean that data type is invalid. It means that the data type contains only positive values. Negative values are not allowed in that data type.

Unsigned data types include:

int, char, short, long.

In C programming language, unsigned is a shortcut to unsigned int data type. That is when we declare a variable as unsigned var; in C language then it by default consider it as int.

Concept:

B- Trees provide a multilevel access structure that is a balanced tree structure in which each node is at-least half full. Each node in a B- tree of order p can have at most p – 1 search values.

Explanation:

Each node in a B- Tree contains a number of ascending values {k₁, k₂, k₃, ……..k_m-1} and pointers {p_1, p₂, …..p_m} where m determines the maximum number of children a node can point to. Value m is the order of the tree.

To maintain the binary search tree property, B- Tree nodes store key values such that all values in the subtree pointed to by p₁ are smaller than k₁.All values in the subtree pointed to by p_i are greater than or equal to k_i and smaller than k_i-1.

Properties of a m- way B – Tree:

1. All leaf nodes must be at same level

2. All nodes except root node must have at-least [m/2]-1 keys and maximum m-1 keys.

3. All non – leaf nodes except the root node must have at least m/2 children.

4. Every node contains at most m children.

5. root must have at least 2 nodes.

Example:

In case of C programming language,

%f stands for float.

%7.2f means to print a float in a field atleast 7 spaces wide but have two digits only after decimal point. So, it will display 123.45.

%7.3f means to print a float in a field atleast 7 spaces wide but after decimal point must have only 3 digits. So, it will display 123.456

%12e – e is used for scientific notation. One digit before the decimal point and must have exponent for scaling purpose. So, it will display 1.234560e +02

Concept:

• A graph G is bipartite if its vertex set can be partitioned into two sets X and Y in such a way that every edge of G has one end vertex in X and the other in Y. In this case, X and Y are called the partite sets.
• A complete bipartite graph is a graph whose vertices can be partitioned into two subsets X and Y such that no edge has both endpoints in the same subset, and every possible edge that could connect vertices in different subsets is part of the graph

K_2,2

1 → 3 → 2 → 4

1 → 4 → 2 → 3

2 → 3 → 1 → 4

3 → 1 → 4 → 2

There are four distinct paths from vertex 1 to vertex 4 which has length 3:

Important point:

Since starting and ending vertex is not specified and very path from vertex 1 to vertex 4 is valid. There 1 → 4 → 2 → 3, 2 → 3 → 1 → 4

and 3 → 1 → 4 → 2 are valid path from vertex 1 to vertex 4 which has length 3.

A path should have distinct edge and vertex.

Tokens are the smallest elements of a program, which are meaningful to the compiler. Tokens types are keywords, identifiers, constant, strings, operators etc.

Number of tokens in the given C language statement is:

Total 8 tokens are possible in this.

1- printf

2- (

3- “The number of tokens are %d”

4- ,

5-&

6- tcount

7-)

8- ;

fopen() opens the file whose pathname is the string pointed to by filename.

There are two parameters in this:

Filename- this is name of the file to be opened

Mode or file type argument – it contains a file access mode.

Various type of file access methods or arguments are:

“r” – opens a file for reading. That file must exist.

“w” – it creates an empty text file for writing. If the file already exists, its contents are destroyed, and file is considered as new file.

“a”- appends to a file. File created if it does not exist.

“r+” – opens a file to update both reading and writing. File must exist

“a+” – Opens a file for reading and append at the end of the file.

“w+” – creates a new file for both reading and writing and destroys the file if a file with the specified file-name already exists in the current directory.