Interviews

whisk somebody/something + adv./prep. to take somebody/something somewhere very quickly and suddenly

fabled: ​famous and often talked about, but rarely seen

A DEC computer refers to machines made by the Digital Equipment Corporation (DEC), a pioneering American company famous for revolutionizing computing with affordable minicomputers.

cling: to hold on tightly to somebody/something

"Bonneville" refers to a significant early programming job Bill Gates and Paul Allen had for the Bonneville Power Administration (BPA) in North Bonneville, Washington, where they debugged software for the Pacific Northwest's electrical grid control system for defense contractor Thompson Ramo Wooldridge (TRW).

awed: showing or feeling respect and slight fear; extremely impressed by somebody/something

bask (in something) to enjoy sitting or lying in the heat or light of something, especially the sun

hone: to develop and improve something, especially a skill, over a period of time

veer: to change direction suddenly

angst: a feeling of great worry about a situation, or about your life

Plymouth was a popular American car brand by Chrysler, launched in 1928 to offer affordable cars against Ford and Chevy, becoming known for reliable models like the Valiant and iconic muscle cars.

Bill Gates "Source Code"

Online Dictionaries Used:

hk.dictionary.search.yahoo.com

www.oxfordlearnersdictionaries.com

Google AI overview

Open a txt file for reading

reading file: ifstream (input file stream)

writing file: ofstream (output file stream)

eof() in C++ is a member function of file stream classes (ifstream, ofstream, fstream) that stands for end-of-file.

stoi in C++ stands for "string to integer".

Meaning of letter = str[0];

str → a std::string object.

• [0] → accesses the first character of the string (indexing starts at 0).
• letter → a variable of type char that stores the result.

So this statement assigns the first character of the string str to the variable letter




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成長

hype: to advertise something a lot and make its good qualities seem better than they actually are, in order to get a lot of public attention for it

conglomerate: (business) a large company formed by joining together different firms

off base: (North American English, informal) completely wrong about something

blurt out: say something suddenly, impulsively, and without thinking, often revealing a secret or a thought you intended to keep hidden, typically due to excitement or nervousness, and sometimes leading to regret

flaw: a mistake in something that means that it is not correct or does not work correctly

fluster: to make somebody nervous and/or confused, especially by giving them a lot to do or by making them hurry

dumb: (especially North American English, informal) stupid

stalk: to walk in an angry or proud way

dread: to be very afraid of something; to fear that something bad is going to happen

congenial: (of a person) pleasant to spend time with because their interests and character are similar to your own

comeuppance: ​a punishment for something bad that you have done, that other people feel you really deserve

cringe: to feel very embarrassed and uncomfortable about something

Bill Gates "Source Code"

Online Dictionaries Used:

hk.dictionary.search.yahoo.com

www.oxfordlearnersdictionaries.com

Working with files

In C++, the fstream class (from the header) is used for both reading and writing files. It combines the functionality of ifstream (input file stream) and ofstream (output file stream), allowing you to open a file and perform input/output operations on it.

The is_open() function in C++ is a member of the file stream classes (ifstream, ofstream, and fstream). It is used to check whether a file stream is currently associated with (and successfully opened) a file.

getline() in C++ — it’s one of the most useful functions for reading text input, especially when dealing with files or user input that includes spaces.

#include <iostream>

#include <string>

using namespace std;

int main() {

    string name;

    cout << "Enter your full name: ";

    getline(cin, name);  // reads entire line including spaces

    cout << "Hello, " << name << "!" << endl;

    return 0;

}




ios::app is a file open mode flag used with file streams (ofstream, fstream).

Meaning: Append mode.

When you open a file with ios::app, all output operations are performed at the end of the file, preserving existing content.

The file pointer is moved to the end before each write.

Existing data is not erased.

console: a flat surface that contains all the controls and switches for a machine, a piece of electronic equipment, etc.

ios::in

• Meaning: Open file for input (reading).
• Behavior:
• The file must exist; otherwise, opening fails.
• You can read data from the file using the stream.
• Typical use: Used with ifstream or fstream.

ios::out

• Meaning: Open file for output (writing).
• Behavior:
• If the file exists, its contents are truncated (erased) unless combined with ios::app.
• If the file doesn’t exist, it is created.
• You can write data into the file.
• Typical use: Used with ofstream or fstream.

The .close() function in C++ is used with file stream objects (ifstream, ofstream, fstream) to close an open file.

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Precocious

sophomore: a student in the second year of a course of study at a college or university

audit something (North American English) to attend a course at college or university but without taking any exams or receiving credit

enthuse: to talk in an enthusiastic and excited way about something

precocious: (of a child) having developed particular abilities and ways of behaving at a much younger age than usual

complimentary: expressing approval, praise, etc.

brat: a person, especially a child, who behaves badly

dejected: unhappy and disappointed

stunned: very surprised or shocked; showing this

propriety: moral and social behavior that is considered to be correct and acceptable

conversant: moral and social behavior that is considered to be correct and acceptable

whizz: to do something very quickly

innate: ​(of a quality, feeling, etc.) that you have when you are born

subtly: in a way that is not very obvious or easy to notice

nerd: ​a person who is boring, stupid and not fashionable

stark: unpleasant; real, and impossible to avoid

deception: the act of deliberately making somebody believe something that is not true

hands-down: easily the winner of a contest; definitely the one that people prefer

suite: a set of rooms, especially in a hotel

confide: to tell somebody secrets and personal information that you do not want other people to know

epiphany: a sudden and surprising moment of understanding

implicit: suggested without being directly expressed

vibe: a mood or an atmosphere produced by a particular person, thing or place

prod: to try to make somebody do something, especially when they are unwilling

languish: to be forced to stay somewhere or suffer something unpleasant for a long time

scrawl: to write something in a careless untidy way, making it difficult to read

vocation: a type of work or way of life that you believe is especially suitable for you

dicey: dangerous and uncertain

Bill Gates "Source Code"

Online Dictionaries Used:

hk.dictionary.search.yahoo.com

www.oxfordlearnersdictionaries.com

Chapter Quiz

A class template allows you to define a class that can work with any data type. Instead of writing separate classes for int, double, string, etc., you write one generic class and let the compiler generate the specific version when you use it

Inheritance allows one class (the derived class) to reuse and extend the functionality of another class (the base class).

Polymorphism means “many forms” — the ability of different classes to be treated through a common interface, often using virtual functions.

In C++ (and in object-oriented programming generally), a superclass is simply another name for a base class — the class that is being inherited from.

A constructor is a special member function that is automatically called when an object of a class is created.

A destructor is a special member function that is automatically called when an object goes out of scope or is deleted.

template <typename T>

size_t size_in_bits(const T& a) {

    return sizeof(a) * 8;

}

template <typename T>

Declares a function template that can accept any type T.

const T& a

The function takes a constant reference to an object of type T.

Using const ensures the function doesn’t modify a.

Using a reference avoids copying large objects.

sizeof(a)

Returns the size of the object a in bytes.

* 8

Converts bytes into bits (since 1 byte = 8 bits).

Return type size_t

A standard unsigned integer type used for sizes.

Queue (FIFO — First In, First Out)

• Think of a line at a ticket counter: the first person to arrive is the first person served.
• Operations:
• Enqueue → add an element at the back.
• Dequeue → remove an element from the front.

Stack (LIFO — Last In, First Out)

• Think of a stack of plates: the last plate you put on top is the first one you take off.
• Operations:
• Push → add an element on top.
• Pop → remove the top element.

What is std::map?

• A sorted associative container in the C++ Standard Library.
• Stores elements as key–value pairs (std::pair).
• Keys are unique (no duplicates).
• Internally implemented as a balanced binary search tree (usually a Red-Black Tree).
• Provides logarithmic time complexity (O(log n)) for insert, search, and delete operations.

What is std::vector?

• A sequence container that stores elements in a contiguous memory block (like an array).
• Unlike arrays, vectors can grow or shrink dynamically.
• Provides random access to elements (constant time O(1) for indexing).
• Efficient insertion/removal at the end (push_back, pop_back are amortized O(1)), but slower at the front or middle (O(n)).

contiguous: touching or next to something

What is std::list?

• A sequence container that stores elements in a doubly linked list.
• Unlike std::vector, elements are not stored contiguously in memory.
• Provides fast insertion and deletion anywhere in the list (O(1) if you already have the iterator).
• Slower random access (O(n)), since you must traverse nodes sequentially.

 What is std::priority_queue?

• A container adapter in the C++ Standard Library.
• Works like a queue, but instead of FIFO order, it always keeps the largest (or highest priority) element at the front by default.
• Internally implemented using a heap (usually a max-heap).
• Provides logarithmic time complexity (O(log n)) for insertion and removal, and constant time O(1) for accessing the top element.

Pointer

• A pointer is a variable that stores the memory address of another variable.
• You can use it to directly access and manipulate memory.

int x = 10;

int* p = &x;   // p points to x

cout << *p;    // dereference → prints 10

*p → dereference (access value at address).

&x → address-of operator.

Pointers can be incremented/decremented to move through contiguous memory (like arrays).

Iterator

• An iterator is an object that behaves like a pointer but is designed to work with STL containers (vector, list, map, etc.).
• Provides a uniform way to traverse containers without worrying about their internal structure.

In computer science, traversing means systematically visiting or accessing every element in a data structure (like an array, tree, or graph) to process it, often using loops or specific algorithms.

#include <vector>

#include <iostream>

using namespace std;

int main() {

    vector<int> v = {1, 2, 3, 4};

    // Iterator

    vector<int>::iterator it;

    for (it = v.begin(); it != v.end(); ++it) {

        cout << *it << " ";  // dereference iterator

    }

}

begin() → returns iterator to first element.

end() → returns iterator past the last element.

Iterators can be incremented (++it) to move forward.

Some iterators support random access (like pointers in vector), while others only support sequential traversal (like in list).

Operator overloading in C++ lets you redefine how operators (like +, -, ==, [], etc.) behave for your own classes. It’s a powerful way to make user-defined types feel natural and intuitive to use.

Normally, operators work with built-in types (int, double, etc.).

With operator overloading, you can extend them to work with objects.

Example: Adding two Complex numbers with + instead of writing a function like add(c1, c2).

Complex numbers are numbers of the form a+bi, where a is the real part, b is the imaginary part, and i is the imaginary unit defined by i^2=-1. They extend the real number system to allow solutions to equations like x^2+1=0, which have no real solutions.

Microsoft Copilot

competition among elite

dazzle: dazzle (somebody) if a strong light dazzles you, it is so bright that you cannot see for a short time

camaraderie: a feeling of friendship and trust among people who work or spend a lot of time together

footing: the basis on which something is established or organized

excel: to be very good at doing something

outlier: a person or thing that is different from or in a position away from others in the group

awkward: difficult to deal with

nudge: a slight push, usually with the elbow

premed: (especially North American English) a course or set of classes that students take in preparation for medical school

intently: with strong interest and attention

monstrous: very large

agilely: (of the way someone or something moves) quickly and easily

intimidating: ​frightening in a way that makes a person feel less confident

crammer: ​a school or book that prepares people quickly for exams

maniacal: ​wild or violent

gobble: to eat something very fast, in a way that people consider rude or greedy

preoccupied: thinking and/or worrying continuously about something so that you do not pay attention to other things

dingy: dark and dirty

grimy: ​covered with dirt

stunned: ​very surprised or shocked; showing this

screwed: in very bad trouble or difficulty

Bill Gates "Source Code"

Online Dictionaries Used:

hk.dictionary.search.yahoo.com

www.oxfordlearnersdictionaries.com

dictionary.cambridge.org