By using the string function find to find the index of a space; the function length to find the length of the string; and the function substr from a file form firstname, middlename, and lastname to lastname, middlename, and first name. Please help me this is c++ thank you
In: Computer Science
Could i please have some assistance with the following
questions.
a) What are key features of UDP Services?
b) What are some of the advantages of UDP compared to TCP?
c) What is the aim of the connection setup Phase, ie, 3 way handshake, of TCP?
d) What causes duplicate ACK's
In: Computer Science
In worm, what will happen if the ssh.connect(...) line fails? What code should be added in order to properly handle such scenarios?
In: Computer Science
Modulation and Encoding
1. Telephone channels have a bandwidth of about 3.1 kHz. Answer the
following questions. (If you like, you can use Excel to do the
calculations and then cut/paste your analysis into your
homework).
a) If a telephone channel’s signal-to-noise ratio (SNR) is 2,000
(the signal strength is 2,000 times as much as the noise strength),
use the Shannon Equation to calculate the maximum data rate of a
telephone channel?
b) How fast could a telephone channel carry data if the SNR were
increased massively, from 2,000 to 20,000? (Note: This would not be
realistic in practice.)
c) With an SNR of 2,000, how fast could a telephone channel carry
data if the bandwidth were increased to 4 kHz? Show your work or no
credit.
d) What do you think is a better way to increase data rate, and
why?
In: Computer Science
Matrix multiplication with arrays
In this question you will verify that the numpy.ndarray matrix multiplication operator, @, does a proper matrix multiplcation. To do this, first write a function, mat_mult(a1, a2) that creates a new 2d array of zeros, and using nested for loops, fill in the elements of the matrix multiplication, and return this new array.
Then, write a second function, matrix_diff(b, c) that takes two arrays as arguments then generates and returns the following ratio:
sqrt((∑(??,?−??,?)^2)/(∑(??,?+??,?)^2))
This function gives a measure of how different two arrays are, giving 0 if the arrays are identical.
Your functions can assume that both matrix arguments are two-dimensional, but they should check that the shapes are compatible and return None if they are not.
In: Computer Science
Write a python function comparing two binary trees and returns whethere they are same. Input two binary tress and output true or false. True= They are the same, False= They are not . Test the function .
In: Computer Science
Compare and contrast Web applications and native applications.
When should a native application be selected over a Web application and vice versa?
What advantage does one have over the other? • What are the disadvantages or limitations of each?
Provide URL of your sources.
In: Computer Science
Assign a new alphabet whenever it sees a new number in those expressions ( Use increment operator(++) so, lets say if x = "a", then x++ would be "b" and so on for as many numbers are there in expressions)
Assignment:Consider the input file “p4in.txt”has the following
contents (in java language)
(Assuming that all expressions are correct): so using the
valueStack ,uses ArrayStack and operatorStack
Specifications:
1) You must implement ArrayStack.java and modify Positfix.java so that valueStack uses ArrayStack and operatorStack uses LinkedStack.
2) Do this program step by step.
3) It may be easier to use String to split the expression to obtain the array of values.
4) Build your symbol table using single-letter variable name that starts from ‘a’.
Here is the inputfile (p4in.txt)
2 + 3
(2+ 3) * 4
2 * 3 / (4 -5)
2 / 3 + (4 -5)
2 / 3 + c -d
2 ^ 3 ^ 4
(2 ^ 3) ^ 4
2 * (3 / 4 + 5)
(2 + 3) / (4 -5)
2 / (3 -4) * 5
2 - (3 / (4 - 5) * 6 + 0) ^ 1
(2 - 3 * 4) / (5 * 6 ^ 0) * 1 + 8
I need to produce the output file named “p4out.txt” similar
to the following:
Here is the output sample p4out.txt
Symbol Table
Variable Value
a
2
b
3
c
4
d
5
e
6
f
0
g
1
h
8
Input
Infix Postfix Result
2 +
3
a+b
ab+ 5
(2+ 3) *
4
(a+b)*c ab+c* 20
2 * 3 / (4
-5)
all value Omitted downhere
2 / 3 + (4 -5)
2 / 3 + c -d
2 ^ 3 ^ 4
(2 ^ 3) ^ 4
2 * (3 / 4 + 5)
(2 + 3) / (4 -5)
2 / (3 -4) * 5
2 - (3 / (4 - 5) * 6 + 0) ^ 1
(2 - 3 * 4) / (5 * 6 ^ 0) * 1 + 8
Required programs:
ArrayStack.java:
import java.util.Arrays;
import java.util.EmptyStackException;
/**
A class of stacks whose entries are stored in an array.
@author Frank M. Carrano
@author Timothy M. Henry
@version 4.0
*/
public final class ArrayStack<T> implements StackInterface<T>
{
private T[] stack; // Array of stack entries
private int topIndex; // Index of top entry
private boolean initialized = false;
private static final int DEFAULT_CAPACITY = 50;
private static final int MAX_CAPACITY = 10000;
public ArrayStack()
{
this(DEFAULT_CAPACITY);
} // end default constructor
public ArrayStack(int initialCapacity)
{
checkCapacity(initialCapacity);
// The cast is safe because the new array contains null entries
@SuppressWarnings("unchecked")
T[] tempStack = (T[])new Object[initialCapacity];
stack = tempStack;
topIndex = -1;
initialized = true;
} // end constructor
public void push(T newEntry)
{
checkInitialization();
ensureCapacity();
stack[topIndex + 1] = newEntry;
topIndex++;
} // end push
public T peek()
{
checkInitialization();
if (isEmpty())
throw new EmptyStackException();
else
return stack[topIndex];
} // end peek
public T pop()
{
checkInitialization();
if (isEmpty())
throw new EmptyStackException();
else
{
T top = stack[topIndex];
stack[topIndex] = null;
topIndex--;
return top;
} // end if
} // end pop
public boolean isEmpty()
{
return topIndex < 0;
} // end isEmpty
public void clear()
{
checkInitialization();
// Remove references to the objects in the stack,
// but do not deallocate the array
while (topIndex > -1)
{
stack[topIndex] = null;
topIndex--;
} // end while
// Assertion: topIndex is -1
} // end clear
// Throws an exception if this object is not initialized.
private void checkInitialization()
{
if (!initialized)
throw new SecurityException ("ArrayStack object is not initialized properly.");
} // end checkInitialization
// Throws an exception if the client requests a capacity that is too large.
private void checkCapacity(int capacity)
{
if (capacity > MAX_CAPACITY)
throw new IllegalStateException("Attempt to create a stack " +
"whose capacity exceeds " +
"allowed maximum.");
} // end checkCapacity
// Doubles the size of the array stack if it is full
// Precondition: checkInitialization has been called.
private void ensureCapacity()
{
if (topIndex >= stack.length - 1) // If array is full, double its size
{
int newLength = 2 * stack.length;
checkCapacity(newLength);
stack = Arrays.copyOf(stack, newLength);
} // end if
} // end ensureCapacity
} // end ArrayStack
LinkedStack.java:
import java.util.EmptyStackException;
/**
A class of stacks whose entries are stored in a chain of nodes.
@author Frank M. Carrano
@author Timothy M. Henry
@version 4.0
*/
public final class LinkedStack<T> implements StackInterface<T>
{
private Node topNode; // References the first node in the chain
public LinkedStack()
{
topNode = null;
} // end default constructor
public void push(T newEntry)
{
topNode = new Node(newEntry, topNode);
// Node newNode = new Node(newEntry, topNode);
// topNode = newNode;
} // end push
public T peek()
{
if (isEmpty())
throw new EmptyStackException();
else
return topNode.getData();
} // end peek
public T pop()
{
T top = peek(); // Might throw EmptyStackException
assert (topNode != null);
topNode = topNode.getNextNode();
return top;
} // end pop
/*
// Question 1, Chapter 6: Does not call peek
public T pop()
{
if (isEmpty())
throw new EmptyStackException();
else
{
assert (topNode != null);
top = topNode.getData();
topNode = topNode.getNextNode();
} // end if
return top;
} // end pop
*/
public boolean isEmpty()
{
return topNode == null;
} // end isEmpty
public void clear()
{
topNode = null; // Causes deallocation of nodes in the chain
} // end clear
private class Node
{
private T data; // Entry in stack
private Node next; // Link to next node
private Node(T dataPortion)
{
this(dataPortion, null);
} // end constructor
private Node(T dataPortion, Node linkPortion)
{
data = dataPortion;
next = linkPortion;
} // end constructor
private T getData()
{
return data;
} // end getData
private void setData(T newData)
{
data = newData;
} // end setData
private Node getNextNode()
{
return next;
} // end getNextNode
private void setNextNode(Node nextNode)
{
next = nextNode;
} // end setNextNode
} // end Node
} // end LinkedStack
Postfix.java:
/**
A class that represents a postfix expression.
Based on pseudocode in Segments 5.16 and 5.18.
@author Frank M. Carrano
@author Timothy M. Henry
@version 4.0
*/
public class Postfix
{
/** Creates a postfix expression that represents a given infix expression.
Segment 5.16.
@param infix A string that is a valid infix expression.
@return A string that is the postfix expression equivalent to infix. */
public static String convertToPostfix(String infix)
{
StackInterface<Character> operatorStack = new LinkedStack<Character>();
StringBuilder postfix = new StringBuilder();
int characterCount = infix.length();
char topOperator;
for (int index = 0; index < characterCount; index++)
{
boolean done = false;
char nextCharacter = infix.charAt(index);
if (isVariable(nextCharacter))
postfix = postfix.append(nextCharacter);
else
{
switch (nextCharacter)
{
case '^':
operatorStack.push(nextCharacter);
break;
case '+': case '-': case '*': case '/':
while (!done && !operatorStack.isEmpty())
{
topOperator = operatorStack.peek();
if (getPrecedence(nextCharacter) <= getPrecedence(topOperator))
{
postfix = postfix.append(topOperator);
operatorStack.pop();
}
else
done = true;
} // end while
operatorStack.push(nextCharacter);
break;
case '(':
operatorStack.push(nextCharacter);
break;
case ')': // Stack is not empty if infix expression is valid
topOperator = operatorStack.pop();
while (topOperator != '(')
{
postfix = postfix.append(topOperator);
topOperator = operatorStack.pop();
} // end while
break;
default: break; // Ignore unexpected characters
} // end switch
} // end if
} // end for
while (!operatorStack.isEmpty())
{
topOperator = operatorStack.pop();
postfix = postfix.append(topOperator);
} // end while
return postfix.toString();
} // end convertToPostfix
// Indicates the precedence of a given operator.
// Precondition: operator is a character that is (, ), +, -, *, /, or ^.
// Returns an integer that indicates the precedence of operator:
// 0 if ( or ), 1 if + or -, 2 if * or /, 3 if ^,
// -1 if anything else. */
private static int getPrecedence(char operator)
{
switch (operator)
{
case '(': case ')': return 0;
case '+': case '-': return 1;
case '*': case '/': return 2;
case '^': return 3;
} // end switch
return -1;
} // end getPrecedence
private static boolean isVariable(char character)
{
return Character.isLetter(character);
} // end isVariable
/** Evaluates a postfix expression.
Segment 5.18
@param postfix a string that is a valid postfix expression.
@return the value of the postfix expression. */
public static double evaluatePostfix(String postfix)
{
StackInterface<Double> valueStack = new LinkedStack<Double>();
int characterCount = postfix.length();
for (int index = 0; index < characterCount; index++)
{
char nextCharacter = postfix.charAt(index);
switch(nextCharacter)
{
case 'a': case 'b': case 'c': case 'd': case 'e':
valueStack.push(valueOf(nextCharacter));
break;
case '+': case '-': case '*': case '/': case '^':
Double operandTwo = valueStack.pop();
Double operandOne = valueStack.pop();
Double result = compute(operandOne, operandTwo, nextCharacter);
valueStack.push(result);
break;
default: break; // Ignore unexpected characters
} // end switch
} // end for
return (valueStack.peek()).doubleValue();
} // end evaluatePostfix
private static double valueOf(char variable)
{
switch (variable)
{
case 'a': return 2.5;
case 'b': return 3.0;
case 'c': return 4.0;
case 'd': return 12.0;
case 'e': return 16.5;
} // end switch
return 0; // Unexpected character
} // end valueOf
private static Double compute(Double operandOne, Double operandTwo, char operator)
{
double result;
switch (operator)
{
case '+':
result = operandOne.doubleValue() + operandTwo.doubleValue();
break;
case '-':
result = operandOne.doubleValue() - operandTwo.doubleValue();
break;
case '*':
result = operandOne.doubleValue() * operandTwo.doubleValue();
break;
case '/':
result = operandOne.doubleValue() / operandTwo.doubleValue();
break;
case '^':
result = Math.pow(operandOne.doubleValue(), operandTwo.doubleValue());
break;
default: // Unexpected character
result = 0;
break;
} // end switch
return result;
} // end compute
} // end Postfix
StackInterface.java:
/**
An interface for the ADT stack.
@author Frank M. Carrano
@author Timothy M. Henry
@version 4.0
*/
public interface StackInterface<T>
{
/** Adds a new entry to the top of this stack.
@param newEntry An object to be added to the stack. */
public void push(T newEntry);
/** Removes and returns this stack's top entry.
@return The object at the top of the stack.
@throws EmptyStackException if the stack is empty before the operation. */
public T pop();
/** Retrieves this stack's top entry.
@return The object at the top of the stack.
@throws EmptyStackException if the stack is empty. */
public T peek();
/** Detects whether this stack is empty.
@return True if the stack is empty. */
public boolean isEmpty();
/** Removes all entries from this stack. */
public void clear();
} // end StackInterface
Driver.java:
/**
A driver that demonstrates the class Postfix.
@author Frank M. Carrano
@author Timothy M. Henry
@version 4.1
*/
public class Driver
{
public static void main(String[] args)
{
System.out.println("Testing postfix expressions with\n" +
"a = 2, b = 3, c = 4, d = 5, e = 6\n\n");
testPostfix("a+b");
testPostfix("(a + b) * c");
testPostfix("a * b / (c - d)");
testPostfix("a / b + (c - d)");
testPostfix("a / b + c - d");
testPostfix("a^b^c");
testPostfix("(a^b)^c");
testPostfix("a*(b/c+d)");
System.out.println("Testing Question 6, Chapter 5:\n");
testPostfix("(a+b)/(c-d)"); // Question 6a, Chapter 5
testPostfix("a/(b-c)*d"); // Question 6b
testPostfix("a-(b/(c-d)*e+f)^g"); // Question 6c
testPostfix("(a-b*c)/(d*e^f*g+h)"); // Question 6d
System.out.println("Testing Question 7, Chapter 5:\n");
System.out.println("Q7a: ae+bd-/ : " + Postfix.evaluatePostfix("ae+bd-/") + "\n");
System.out.println("Q7b: abc*d*- : " + Postfix.evaluatePostfix("abc*d*-") + "\n");
System.out.println("Q7c: abc-/d* : " + Postfix.evaluatePostfix("abc-/d*") + "\n");
System.out.println("Q7d: ebca^*+d- : " + Postfix.evaluatePostfix("ebca^*+d-") + "\n");
System.out.println("\n\nDone.");
} // end main
public static void testPostfix(String infixExpression)
{
System.out.println("Infix: " + infixExpression);
String postfixExpression = Postfix.convertToPostfix(infixExpression);
System.out.println("Postfix: " + postfixExpression);
System.out.println("\n");
} // end testPostfix
} // end Driver
/*
Testing postfix expressions with
a = 2, b = 3, c = 4, d = 5, e = 6
Infix: a+b
Postfix: ab+
Infix: (a + b) * c
Postfix: ab+c*
Infix: a * b / (c - d)
Postfix: ab*cd-/
Infix: a / b + (c - d)
Postfix: ab/cd-+
Infix: a / b + c - d
Postfix: ab/c+d-
Infix: a^b^c
Postfix: abc^^
Infix: (a^b)^c
Postfix: ab^c^
Infix: a*(b/c+d)
Postfix: abc/d+*
Testing Question 6, Chapter 5:
Infix: (a+b)/(c-d)
Postfix: ab+cd-/
Infix: a/(b-c)*d
Postfix: abc-/d*
Infix: a-(b/(c-d)*e+f)^g
Postfix: abcd-/e*f+g^-
Infix: (a-b*c)/(d*e^f*g+h)
Postfix: abc*-def^*g*h+/
Testing Question 7, Chapter 5:
Q7a: ae+bd-/ : -4.0
Q7b: abc*d*- : -58.0
Q7c: abc-/d* : -10.0
Q7d: ebca^*+d- : 49.0
Done.
*/
In: Computer Science
Native Apps, Web Apps, and Hybrid Apps
Native Apps vs Mobile Web: Breaking Down the Mobile Ecosystem
In: Computer Science
Develop 10 requirements describing a thread of functionality you are familiar with. It can be a work project, a school project, or just something you have an interest in.
In: Computer Science
Write a Python program that prompts the user for a dollar amount to place in savings, the amount of interest per year, and the amount of years you decide to keep it there. The program will calculate how much money you will have each year. Use loops in your calculations and Use the loop below:
for year = 1 to X
savings = savings * interestRate
In: Computer Science
int num=10;
do
{
cout << “Hello” << endl;
num--;
} while(num > 1);
After the above code is executed:
language is c++
In: Computer Science
I have "schedule" (guest, volunteer etc) and "Inventory" (food,bedding,cleaning stuff etc inventory)as an entity so what could be attributes to these two entities? And also give partial and transitive dependencies between the attributes in normalization process? please hurry
In: Computer Science
L ={x^a y^b z^c | c=a+b} a) Prove that L is not regular. b)Prove by giving a context-free grammar that the L is context free. c)Give a regular expression of the complement L'.
In: Computer Science
Write a PYTHON program that uses a while loop to prompt for 5 integers.
If the number is equal to 99, display "Ninety-nine", otherwise display "no-match".
If the number is equal to 75, display "Seventy-five", otherwise display "no-match".
In: Computer Science