Lecture 5: Visual Studio

Learning Outcomes

By the end of this lecture, students should be able to:

• Understand data types and variables in C++.
• Apply various operators and manage data processing effectively.
• Build and execute a C++ project using Visual Studio.

Creating a Project in Visual Studio

1. Start Visual Studio 2022 -> Choose Create a new project.
2. Select Empty Project and give it a name (e.g., Project_NTCU).
3. Choose a save location -> Click Create.
4. In Solution Explorer, a new solution appears with the chosen name.
5. Right-click on Source Files -> Add -> New Item -> C++ File (.cpp).
6. Name it (e.g., first_program.cpp) -> Click Add.
7. To run the program:
   • Press F5 for Start Debugging, or
   • Press Ctrl + F5 for Start Without Debugging.

Debugging Options

• F5 (Start Debugging): Attaches the debugger.
• Ctrl + F5 (Start Without Debugging): Runs without debugging; console remains open.

Tip: To auto-close the console after debugging, go to
Tools -> Options -> Debugging -> Automatically close console when debugging stops.

Resolving main() Conflicts

When multiple .cpp files have main():

1. In Solution Explorer, right-click the file -> Properties.
2. Go to Configuration Properties -> General.
3. Set Excluded from Build = Yes for files that shouldn't be compiled.

Visual Studio Project Structure

File	Description
first_program.cpp	Source code file containing main() and program logic.
Project_NTCU.sln	Solution file that manages all projects within Visual Studio.
Project_NTCU.vcxproj	Project file with compiler and linker settings (XML format).
Project_NTCU.vcxproj.filters	Organizes files visually in the Solution Explorer.
Project_NTCU.vcxproj.user	Stores user-specific settings (e.g., debugging options).

Basic C++ Examples

#include <iostream>
using namespace std;

int main() {
  cout << 9 + 3;
  return 0;
}

Escape Sequences

Escape	Description
\n	New line
\t	Horizontal tab
\\	Backslash
\"	Double quote

Example:

cout << "Hello World!\nI am learning C++";

Comments in C++

Used to improve code readability or disable parts of code.

// Single-line comment

/* Multi-line
   comment */

Variables and Data Types

Variables are containers for storing data. Each variable has a type that defines the kind of data it can hold.

Basic Data Types

Type	Size	Description
int	2–4 bytes	Whole numbers
char	1–2 bytes	Single character (ASCII)
string	24–32 bytes	Text sequences
float	4 bytes	Decimal numbers (6–7 digits precision)
double	8 bytes	Decimal numbers (up to 15 digits precision)
bool	1 byte	true or false

Examples:

int age = 20;
float price = 19.99;
char grade = 'A';
string name = "Othman";
bool isStudent = true;

Numeric and Character Examples

Integer Example:

int x = 20;
cout << "x = " << x;

Float Example:

float myNum = 10.25;
cout << myNum;

Double Example:

double myNum = 10.999999992355;
cout << myNum;

Scientific Notation:

float f1 = 27E3;  // 27000
double d1 = 15e4; // 150000

Character Example:

char myGrade = 'A';
cout << myGrade;

ASCII Example:

char d = 68, b = 66;
cout << d << b; // Outputs DB

Strings

Declaration:

string myText = "Hello, World!";

Concatenation:

string fullName = firstName + lastName;
string mobile = "010" + "99985809";

Using append() Method:

string fullName = firstName.append(lastName);

Combining Numbers and Strings:

string result = "My number is: " + to_string(565655656);

Input Example

int x;
cout << "Type your number: ";
cin >> x;
cout << "Sum = " << x + 5;

Operators

Arithmetic Operators

Operator	Name	Example
+	Addition	x + y
-	Subtraction	x - y
*	Multiplication	x * y
/	Division	x / y
%	Modulus	x % y
++	Increment	++x
--	Decrement	--x

Assignment Operators

Operator	Description	Equivalent
=	Assign	x = 9
+=	Add and assign	x = x + 9
-=	Subtract and assign	x = x - 9
*=	Multiply and assign	x = x * 9
/=	Divide and assign	x = x / 9
%=	Modulus and assign	x = x % 9

Comparison Operators

Operator	Meaning	Example
==	Equal to	x == y
!=	Not equal	x != y
>	Greater than	x > y
<	Less than	x < y
>=	Greater or equal	x >= y
<=	Less or equal	x <= y

Example:

int x = 7, y = 5;
cout << (x == y); // false (0)

Logical Operators

Operator	Name	Description	Example
&&	AND	True if both are true	a < 8 && a < 12
||	OR	True if one is true	a < 9 || a < 10
!	NOT	Reverses result	!(a < 7 && a < 15)

Example:

int a = 8;
cout << (a > 4 && a < 10); // true (1)

Operator Precedence

Priority	Operators
1	()
2	*, /, %
3	+, -
4	>, <, >=, <=
5	==, !=
6	&&
7	||
8	=

Execution Order:

1. Parentheses ()
2. Multiplication/Division/Modulus
3. Addition/Subtraction
4. Comparisons
5. Logical operations

Summary

• Set up and manage C++ projects in Visual Studio.
• Use basic syntax, variables, and data types effectively.
• Apply escape sequences, comments, and operators.
• Understand operator precedence and logical expressions.