The Most Essential C++ Advice for Beginners

C++ is one of the most popular and widely used programming languages in the world. It's a robust, high-performance language that forms the foundation for many applications, games, operating systems and more. However, C++ is also complex with a steep learning curve. Mastering C++ requires dedication and practice.

This guide provides beginner C++ programmers with the most essential advice to start writing, compiling and debugging C++ code effectively. Follow these C++ tips and techniques to go from a complete beginner to an intermediate C++ coder. You can use this guide alongside the JBI training you receive in our acclaimed C++ Introduction training course.

Getting Started with C++

To write your first C++ program, you need a development environment with a compiler and linker to generate an executable file from your code. Here are some steps to set up a C++ dev environment:

Install a Compiler - Popular options include GCC/G++, Microsoft Visual Studio and Clang.
Install a Text Editor - Such as Sublime Text, Atom or Visual Studio Code for writing code.
Learn Command Line Basics - For compiling code and running programs from the terminal.

For example, to compile a simple hello world program in C++, you can use the g++ compiler:


// helloworld.cpp
#include <iostream>
using namespace std;

int main() {
  cout << "Hello World!";
  return 0; 
}


$ g++ helloworld.cpp -o helloworld 
$ ./helloworld
Hello World!

This compiles the source code into an executable file that you can then run.

Mastering Basic C++ Syntax

C++ syntax can seem confusing at first compared to other languages. Here are some key C++ syntax basics you should learn:

Semi-colons - These are used to terminate statements. Forget one and you'll get an error!
Brackets - Curly brackets {} are used to group code blocks like functions. Square brackets [] are used for arrays.
Pointers and References - Indicated with * and & respectively. More on those later!
Header Files - .h files contain reusable component declarations.
Comments - // for single line comments or /* */ for multi-line.

Make sure to understand fundamental syntax like proper indentation, statements termination and brackets. Focus on writing cleanly formatted code.

Working with Operators

Operators allow you to perform operations on variables and values. Some key C++ operators include:

Arithmetic - +, -, *, /, % - for math operations.
Assignment - =, +=, -=, *=, /= - for assigning values.
Comparison - ==, !=, >, < - for comparing two values.
Logical - &&, ||, ! - for combining conditional logic.

For instance, you can perform arithmetic on numbers:


int x = 5;
int y = 2; 
int sum = x + y; // 7
int diff = x - y; // 3

And use comparison operators like greater than (>) in an if statement:


if (x > y) {
  cout << x << " is greater than " << y;
}

Controlling Program Flow

Being able to control how a C++ program executes is essential. Here are some common flow control techniques:

if/else - Execute code based on a condition being true or false.
for loop - Repeat code execution for a set number of iterations.
while loop - Repeat code while a condition remains true.
switch - Select code to run based on a variable's value.

For example, a for loop prints numbers from 1 to 5:

  
for (int i = 1; i <= 5; i++) {
  cout << i << endl; 
}

And a while loop prints numbers till x is no longer less than 10:


int x = 1;
while (x < 10) {
  cout << x << endl;
  x++;   
}

Mastering control flow is key to writing efficient C++ code.

Functions in C++

Functions are reusable blocks of code that group together logic. Here's the syntax to define and call a function in C++:


// Function definition
void printHello() {
  cout << "Hello there!" << endl; 
}

// Calling the function
printHello();

Functions start with a type like void, int or string.
The function name follows, then parentheses for parameters.
The function body is defined inside braces {}.
Calling the function uses just the name and ().

Parameters allow passing data into a function. Return values allow returning data back from a function.

Pointers and References

Pointers and references are important but tricky concepts in C++.

A pointer holds the memory address of another variable:

  
int x = 10;
int* ptr = &x; // ptr holds address of x

While a reference is like an alias to an existing variable:


int x = 10;
int& ref = x; // ref refers to x

Pointers access data indirectly and can be reassigned, while references act as alternative names. Mastering pointers and references is critical for low-level programming in C++.

Classes and Objects

C++ uses classes and objects to implement object oriented programming. A class encapsulates data and functions into one unit:


// Class definition
class Person {
public:
  string name;
  int age;

  void printInfo() {
    //...
  }
};

// Object creation  
Person person1;
person1.name = "John";
person1.age = 20;

The class defines properties (name, age) and methods (printInfo()).
An object like person1 is an instance of that class.
Object properties are accessed using dot syntax like person1.name

OOP is vital to C++ and mastery of classes is essential for C++ programmers.

Arrays and Strings

Arrays allow storing sequential data of the same type. Strings represent textual data.


// Array example
int nums[5] = {1, 2, 3, 4, 5};

// String example  
string greeting = "Hello world!";

Key string operations include:

length() - Get string length
find() - Find substring position
substr() - Extract a substring
+= - Concatenate strings

And array operations include:

Sorting - sort(arr, arr+n)
Iterating - for loops, range-based for
Searching - find(), binary_search()
std::array for fixed size arrays

Practice arrays and strings well as they are very commonly used data structures.

Debugging in C++

No matter how good a coder you become, bugs are inevitable. Here are some tips for debugging C++ code:

Use a debugger like GDB to step through code.
Print output to check values using cout.
Use assertions like assert(x > 0) to catch errors.
Try a different compiler for better error messages.
Break code into smaller functions for modularity.
Comment out sections of code to isolate bugs.
Ensure proper error handling with try/catch blocks.

Take your time to fix bugs one by one. Avoid panicking or rushing when debugging!

Adopting Best Practices

Some final best practices that will make you a better C++ programmer include:

Use consistent and meaningful variable/function names.
Break code into small, single-responsibility functions.
Modularize using classes, namespaces, files.
Document code with clear comments.
Initialize variables and validate input data.
Prefer std:: arrays/vectors over C arrays.
Prevent leaks by managing memory properly.
Keep learning! Read books, do courses and practice.

By following these tips and with regular practice, you will be on your way to mastering C++ in no time!

Frequently Asked Questions

Here are some common FAQs for beginner C++ programmers:

Should I use pointers or references?

Prefer references over pointers for function parameters. Use pointers only when necessary for dynamic memory.

When should I use a class vs struct?

Use classes by default, structs for passive data holding. Classes have private members by default while structs are public.

How do I decide between a for vs while loop?

Use for loops when you know the iteration count. While loops are best when iterations depend on a condition.

What IDE is best for C++ development?

For beginners, CodeBlocks, Xcode or Visual Studio Community are good free options. As you advance, try CLion or Visual Studio.

Summary

C++ is a versatile and powerful language but has a steep learning curve. Be patient, write lots of code and don't hesitate to get help. Using these C++ tips and tricks for beginners, with regular practice, you'll be on the journey to mastering C++.

The key is to start writing small programs hands-on, make mistakes and learn from them. And remember to enjoy the process - after all, programming is fun!

Check out our first article Learn C++ from scratch: A complete guide for beginners or consider one of the courses that we offer

Recommended C++ Courses from JBI Training

C++ Introduction

This foundational C++ course is ideal for complete beginners. It covers core C++ syntax, data types, functions, classes, and other basic concepts. Taking this intro course will give you the core knowledge needed before advancing to more complex C++ topics.