Consider the following syntax when declaring strings in C:

a. string s1; //creates a empty string

b. string s2 = hello; //creates a string initialized to hello.

c. string s3(hello); //creates a string initialized to hello;

//an explicit-valued constructor called.

d. string s4 = s2; //declaration and initialization; the copy constructor

//called.

More information on the string class can be found in your course textbook and on the web.

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5. Experiments

Step 1: In this experiment you will investigate the declaration, initialization and implementation of

C++ styles. Enter, save, compile and execute the following program in MSVS. Call the new

directory cPlusPlusStringsExp1 and the program cPlusPlusStrings1.cpp. Answer the questions

below:

#include

#include

using namespace std;

int main()

{

string my_name = "Thomas Jefferson";

string her_name("Michelle Obama");

string his_name = my_name;

cout<<"my_name = "<

cout<<"The length of my_name is "<

cout<<"The size of my_name is "<

cout<<"her_name = "<

cout<<"The length of her_name is "<

cout<<"The size of her_name is "<

his_name = "Barack Obama";

cout<<"his_name = "<

cout<<"The length of his_name is "<

cout<<"The size of his_name is "<

string their_name;

their_name = my_name + " " + her_name

+ " " + his_name + " " + my_name + " ";

cout<<"their_name = "<

cout<<"The length of their_name is "<

cout<<"The size of their_name is "<

return 0;

}

Question 1:

Please explain why the size and the length values for each string are

different (or the same) in the output produced by the program in Step

1 above?

Question 2:

Why is the size the same for each string in the program in Step 1?

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Question 3:

Please write the statements from the program in Step 1 in which a constructor is

used? Name each constructor.

Question 4:

Please name the string operations that were preformed in the program?

Step 2: In this experiment you will investigate performance of the subscript and the relational

operators on strings. Enter, save, compile and execute the following program in MSVS. Call the

new directory cPlusPlusStringsExp2 and the program cPlusPlusStrings2.cpp. Answer the

questions below:

#include

#include

using namespace std;

int main()

{

string my_name = "Thomas Jefferson";

string her_name("Michelle Obama");

string his_name = "Joe Biden";

for (int i=0; i < her_name.length(); i++)

{

cout<

}

cout<

if (my_name == "Thomas Jefferson")

{

cout << "my_name is equal to Thomas Jefferson"

<< endl << endl;

}

if (my_name > her_name)

{

cout << my_name <<" is lexicographically greater than "

<< her_name << endl << endl;

}

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if (my_name < his_name)

{

cout << my_name <<" is lexicographically less than "

<< his_name <

}

if (my_name >= her_name)

{

cout << my_name <<" is lexicographically greater than or equal to "

<< her_name << endl << endl;

}

if (my_name <= his_name)

{

cout << my_name <<" is lexicographically less than or equal to "

<< his_name <

}

return 0;

}

Question 5:

What does the for loop do in the program in Step 2?

Question 6:

Please explain the operation of each relational operator used in the program in Step

2?

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Step 3: In this experiment you will investigate the performance of the find and substring functions.

Enter, save, compile and execute the following program in MSVS. Call the new directory

cPlusPlusStringsExp3 and the program cPlusPlusStrings3.cpp. Answer the questions

below:

#include

#include

using namespace std;

int main()

{

string s1 = "123abc456de111ef789eehij111ee";

string s2;

int loc = 0;

for (int i =0; i

{

loc = s1.find("1",loc);

if (loc != -1)

{

cout<<"1 appears at location "<

loc++;

}

}

cout << endl << endl;

s2 = s1.substr(0,3);

cout << "s2 equals " << s2<

s2 = s1.substr(3,3);

cout << "s2 equals " << s2<

s2 = s1.substr(0,500);

cout << "s2 equals " << s2 << endl << endl;

loc = 0;

s2 = "";

for (int i =0; i

{

loc = s1.find("e",loc);

if (loc != -1)

{

s2+= s1.substr(loc,1);

loc++;

}

}

cout << "s2 equals " << s2 << endl <

return 0;

}

Question 7:

What compiler warnings were given?

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Question 8:

What does the first

for

loop perform in the program in Step 3? Explain by observing

the output of the program.

Question 9:

Please explain

the first three statements

that use the substr function?

Question 10:

Please explain the last for loop in the program?

PLEASE ONLY ANSWER QUESTIONS 1 THROUGH 10 !!! PLEASE ANY OTHER ANSWERS WILL BE REPORTED AS SPAM; otherwise, a 5 stars :)