Question

Consider the definition of the following function template: template Type funcExp(Type list[], int size) { int j; Type x = list[0]; Type y = list[size - 1]; for (j = 1; j < (size - 1)/2; j++) { if (x < list[j]) x = list[j]; if (y > list[size – 1 – j]) y = list[size – 1 – j]; } return x + y; } Further suppose that you have the following declarations: int list[10] = {5, 3, 2, 10, 4, 19, 45, 13, 61, 11}; string strList[] = {"One", "Hello", "Four", "Three", "How", "Six"}; What is the output of the following statements? a. cout << funExp(list, 10); b. cout << funExp(strList, 6) << endl;

Short answer

a. 21 b. OneHow

Step-by-step solution

Analyze the function for integer input

The function `funcExp` is invoked with `list` and `size = 10`. Initially, `x` is set to `list[0]` (5) and `y` is set to `list[9]` (11). The loop iterates from `j = 1` up to `j = 3` because the upper limit is `(size - 1)/2 = 4.5`, which rounds down to 3 in integer division.

Iterate and update variables for integer list

For each iteration, update `x` to the maximum of current `x` and `list[j]` and update `y` to the minimum of current `y` and `list[size - 1 - j]`. After evaluations: - For `j = 1`: x = max(5, 3) = 5, y = min(11, 61) = 11 - For `j = 2`: x = max(5, 2) = 5, y = min(11, 13) = 11 - For `j = 3`: x = max(5, 10) = 10, y = min(11, 45) = 11.

Calculate result for integer input

After completing the loop, add `x` and `y`. Therefore, the result is `x + y = 10 + 11 = 21` for the integer input.

Analyze the function for string input

The function `funcExp` is invoked with `strList` and `size = 6`. Initially, `x` is set to `strList[0]` ("One") and `y` is set to `strList[5]` ("Six"). The loop iterates from `j = 1` up to `j = 2`.

Iterate and update variables for string list

For each iteration, compare strings lexicographically and update `x` and `y` accordingly: - For `j = 1`: x = max("One", "Hello") = "One", y = min("Six", "How") = "How" - For `j = 2`: x = max("One", "Four") = "One", y = min("How", "Three") = "How".

Calculate result for string input

After completing the loop, concatenate `x` and `y`. Therefore, the result is `x + y = "One" + "How" = "OneHow"` for the string input.

Key concepts

C++ Programming

The C++ programming language is a versatile language used for a variety of applications, from systems programming to game development.
Function templates, like the one featured in this exercise, allow us to write generic and reusable code.
Using the `template ` helps in creating a function that can operate with any data type.
This takes away the redundancy of writing multiple versions of a function for different data types.
When the function is called, C++ automatically deduces the correct type based on the arguments passed.

• This promotes code efficiency.
• It simplifies maintenance.
• Templates make programs shorter and easier to read.

In our exercise, `funcExp` is a template function that takes an array and its size, finds specific values, and returns their sum or concatenation, depending on the data type.
Understanding function templates is key for any budding C++ programmer. It highlights the power and flexibility of C++ programming structures.

Array Manipulation

Arrays in C++ serve as a way to store multiple items of the same type.
They are passed to functions as a pointer to the first element.
In the function `funcExp`, we manipulate arrays by iterating over their elements.
Array manipulation allows for dynamic changes and calculations over batches of data. Common manipulations include iterating, finding max/min values, and modifying items.
Within `funcExp`, the function initializes two variables, `x` and `y`, to hold the first and last element respectively.
As it iterates through the array, it updates `x` to be the maximum value in the first part of the list and `y` to be the minimum value in the latter.

• Efficient handling of data by indexing.
• Consistent access time for elements.
• Appropriate for batch data operations.

This manipulation is essential for achieving the function's purpose, demonstrating the efficiency of arrays in data handling.

Lexicographical Comparison

Lexicographical comparison is akin to dictionary ordering for strings, where each character is compared sequentially based on their ASCII values.
In C++, this is achieved using the `<` and `>` operators.
In the provided exercise, when `funcExp` is used with a string array, string comparison comes into play.
Strings are compared element by element until a difference is found.
For example, in comparing 'Hello' and 'One', it checks each letter from the start and determines which is "greater" or "smaller" in a lexicographical sense.

• Useful for sorting strings.
• Performing checks or operations based on string order.
• Critical for string manipulation tasks in C++.

The operation performed in `funcExp`, when paired with strings, results in concatenating the lexicographically greatest and smallest strings, exhibiting how pivotal proper comparison is in achieving the desired function outcome.
This understanding aids in designing better string operations and algorithms in C++ applications.