Until an access specifier is given, all class members are implicitly private. All members defined after an access specifier is used will will have that access level until another access specifier is explicitly invoked. Since no access specifier was used, weight and height are automatically private. 

Note that virtual is not an access keyword.

This clock class is defined as having only seconds in its fields, so you have to convert this value for any of the accessors and mutators. Therefore, you need to perform careful (though simple) mathematics for this conversion. To calculate the number of minutes in a given number of seconds, you first need to remove the hours from total count. First, compute the hours using integer division (which will drop the fractional portion of the decimal). This is:

int hours = seconds / 3600;

Next, you need to figure out how many seconds are in that value of hours. This is helpful precisely because integer division drops the decimal portion. Thus, you will subtract off:

hours * 3600

from the total seconds.

This gives you the seconds that apply to the minutes and seconds of the time. Therefore, you will finally need to divide by 60 to isolate the minutes.

There are several points to be noted in this code. First, you need to calculate each of the constituent parts from the seconds stored in the class. The "display value" of seconds is relatively easy. This is just the remainder of a division by 60.  Consider:

61 seconds => This is really 1 minute and 1 second.

155 seconds => This is really 2 minutes and 35 seconds.

So, you know that the display seconds are:

seconds % 60

You must compute the hours using integer division (which will drop the fractional portion of the decimal).  This is:

int hours = seconds / 3600;

Next, you need to figure out how many seconds are in that value of hours.  This is helpful precisely because integer division drops the decimal portion.  Thus, you will subtract off:

hours * 3600

from the total seconds.

This gives you the seconds that apply to the minutes and seconds of the time. Therefore, you will finally need to divide by 60 to isolate the minutes.

Then, you must pad the values.  This is not done using +=, which would add the "0" character to the end of the string. Instead, it is done by the form:

secString = "0" + secString;

A "for each" loop was introduced in C++ 11 which allows the user to loops through a container of items without writing a traditional loop. Let's take a look at all the choices.

for( int i : intVec(){

    i * = 2;

}

Although this looks like the correct answer, it's not. The int i in the first part of the for loop is passed in "by value", which means that a copy of intVec will be made and the integers inside the copy will be doubled. The integers inside the original intVec vector will be unaffected. To fix this problem, int i needs to be passed into the for loop "by reference", which is done by adding a "&" symbol after "int".

The correct loop is:

for( int& i : intVec(){

    i * = 2;

}

Let's take a look at the other choices:

for( int& i : intVec(){

    i = 2;

}

This one will not work because it is setting all items in intVec to 2, not doubling them.

All the other for loops are not "for each" loops so they are incorrect even if they accomplish the same output.

The first part of fun assigns the value of the last location of the array to the first location. Then, it returns the a[0] + (a[0] % 2). That last portion will be a "1" if a[0] is odd, and "0" if a[0] is even. Since a[0] == 12, which is even, the expression evaluates to 12 + 0, which is 12.

The loop will run 5 times. The values of x, y, and z after each run will be as follows:

• i == 0: x == 7,   y == 1,   z == 7 
• i == 1: x == 8,   y == 6,   z == 8 
• i == 2: x == 14, y == 2,   z == 14 
• i == 3: x == 16, y == 12, z == 16
• i == 4: x == 28, y == 4,   z == 28

At the end, i will equal 5, and the values will no longer change.

The .substring() method takes the character at the first number in the arguments, and goes through the String until it reaches the second number in the arguments, without copying the character at the second number.

In the first part of mystery(), the Strings s1, s2, s3, s4, and s5 are made and filled. If n = # of characters in s, s1 gets the first character in s, s2 gets the second character in s, s3 gets the third through n-2 characters, s4 gets the n-1 character, and s5 gets the last character.

Let's look at the second portion of mystery(). 

if (s.length() <= 5)
     return s5 + s4 + s3 + s2 + s1;
else
     return s1 + s2 + mystery(s3) + s4 + s5;

The if statement checks the length of s, and if it's less than or equal to 5, it returns a String made from s5, followed by s4, etc. If s were equal to "abcde", then the if would evaluate to true, and would return "edcba". In recursion, this is known as the "base case".

The else statement is for strings that are greater than 5 characters in length. It returns s1, followed by s2, then the result of mystery(s3), then s4 and s5. The fact that it calls itself makes this recursion. 

Let's step through the example. The argument for mystery(), s, is "ABNORMALITIES". After the first part, this is the result:

We start with an array, arr, of size 5, containing {1, 2, 3, 4, 5}. 

The loop in the code,

for (int i = 0; i < arr.length - 2; i++)

loops through the array up to the second to last cell, given that arr.length - 2 is the index of the second to last cell, and it starts at the first cell. 

Let's look at the code inside the loop.

When i = 2

As the loop progresses, it moves whatever value is in arr[0] all the way to the end of the array.

The user could input a string and the cast to an (Integer) would cause a runtime exception. If there is a runtime exception, the program will stop and open up vulnerabilities to hackers. Once a hacker knows how to halt a program, they can start input bad data to see a database schema to collect data. One way to fix this would be using a utility method such as parseInt(ui). 

This code fills up the 6 member array with alternating Rectangle and Square objects. You can do this because the Square class is a subclass of Rectangle. That is, since Squares are Rectangles, you can store Square objects in Rectangle variables. However, even though rects[1] is a square, you CANNOT immediately reassign that to a Square object. The code has now come to consider all of the objects in the array as being Rectangle objects. You would need to explicitly type cast this to get the line to work:

Square s = (Square)(rects[1]);