In this section, we will cover the fundamental building blocks of C++ programming: variables, data types, operators, and control structures. These concepts are essential for understanding how to write basic programs in C++. Let's dive in!

Variables

Variables are used to store data in a program. They have a data type that determines the kind of data they can hold. In C++, you need to declare a variable before you can use it. Here's an example:

1#include <iostream>
2
3int main() {
4  int age = 25;
5  std::cout << "I am " << age << " years old" << std::endl;
6  return 0;
7}

The above code declares an integer variable age and assigns it the value 25. It then prints a message using the std::cout object and the insertion operator <<.

Data Types

C++ provides several built-in data types for different kinds of values. Here are some common data types:

• int: for integers
• double: for floating-point numbers
• bool: for true or false values
• char: for single characters

For example, you can declare and initialize variables of different data types like this:

1int x = 10;
2double pi = 3.1415;
3bool flag = true;
4char c = 'A';

Operators

Operators are used to perform operations on variables and values. C++ provides various types of operators, including arithmetic, assignment, comparison, logical, and bitwise operators. Here are some examples:

• Arithmetic operators: + (addition), - (subtraction), * (multiplication), / (division), % (modulus)
• Assignment operators: = (assignment), += (addition assignment), -=, *=, /=, %= (similar for other operators)
• Comparison operators: == (equal to), != (not equal to), > (greater than), < (less than), >= (greater than or equal to), <= (less than or equal to)
• Logical operators: && (logical AND), || (logical OR), ! (logical NOT)

Control Structures

Control structures allow you to control the flow of execution in a program. C++ supports several control structures, including:

• if statement: executes a block of code if a certain condition is true
• else statement: executes a block of code if the condition of an if statement is false
• for loop: executes a block of code repeatedly for a specified number of times
• while loop: executes a block of code repeatedly as long as a certain condition is true

Here's an example that uses a control structure:

1#include <iostream>
2
3int main() {
4  int x = 5;
5
6  if (x > 0) {
7    std::cout << "x is positive" << std::endl;
8  } else {
9    std::cout << "x is non-positive" << std::endl;
10  }
11
12  return 0;
13}

The code checks if the value of the variable x is greater than 0 and prints a message accordingly.

These are just the basics of C++ syntax, but they form the foundation for more complex programming concepts. Make sure you understand these concepts thoroughly before moving on to more advanced topics.

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#include <iostream>

​

int main() {

  // Your code here

  return 0;

}