Lesson 4: Conditional Logic: if, else if, else & switch-case

🔀 Decision Making in C++

Control flow statements allow your program to branch dynamically based on variable values or conditional evaluation.

💡 Syntax Structure: if-else vs switch-case

🎯 if / else if / else: Best for evaluating complex range conditions or boolean expressions (gpa >= 3.5 && credits > 60).

⚡ switch (expression): Optimized jump table generated by the compiler for testing discrete integer or enum values (case 1:, case 2:).

💻 Code Example: Grading & Calculator Engine

⊞C++ Source Code (main.cpp)

#include <iostream>

int main() {

char option;

std::cout << "Choose Operation [A: Addition, S: Subtraction, M: Multiplication]: ";

std::cin >> option;

double num1 = 50.0, num2 = 10.0;

switch (toupper(option)) {

case 'A':

std::cout << "Result: " << (num1 + num2) << std::endl;

break;

case 'S':

std::cout << "Result: " << (num1 - num2) << std::endl;

break;

case 'M':

std::cout << "Result: " << (num1 * num2) << std::endl;

break;

default:

std::cout << "Invalid Option Selected!" << std::endl;

break;

}

return 0;

}

⊞Windows 11 Pro Terminal Execution OutputWindows 11 Pro Verified

⊞Administrator: Windows 11 Pro Command Prompt (g++ GCC 13.2.0)

—□✕

Microsoft Windows [Version 10.0.22631.3007] (Windows 11 Pro x86_64)

C:\Users\Student\CPP_Project>#include <iostream>

C:\Users\Student\CPP_Project> g++ -o main.exe main.cpp C:\Users\Student\CPP_Project> main.exe Hello World from C++ on Windows 11 Pro! [Process exited with code 0 in 0.001 seconds]

> 💡 Developer Joke: Why did the C++ developer get lost in the city?

> Because they couldn't find the default: case! 😂

🔀 Decision Making in C++

💡 Syntax Structure: if-else vs switch-case

💻 Code Example: Grading & Calculator Engine

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