Lesson 8: C-Style Arrays vs Dynamic std::vector in Modern C++

📦 Array Storage & Dynamic Containers

In C++, contiguous memory storage is fundamental. You can use fixed-size C-style arrays or flexible dynamic std::vector containers from the Standard Template Library (STL).

⚖️ Fixed C-Style Array vs Dynamic std::vector

📌 C-Style Array (int arr[5];): Fixed size set at compile-time. Resides on Stack. Danger of buffer overflow if bounds are exceeded.

🚀 std::vector<T>: Dynamically resizes on the Heap as elements are added via push_back(). Provides bounds checking (vec.at(i)), size tracking (vec.size()), and auto memory management.

💻 Code Example: Dynamic Vector Operations

⊞C++ Source Code (main.cpp)

#include <iostream>

#include <vector>

#include <algorithm>

int main() {

std::vector<int> scores = {88, 95, 72, 99, 84};

// Add new dynamic elements

scores.push_back(100);

scores.push_back(91);

// Sort vector using STL algorithm

std::sort(scores.begin(), scores.end());

std::cout << "--- Sorted Student Scores (Total: " << scores.size() << ") ---" << std::endl;

for (size_t i = 0; i < scores.size(); ++i) {

std::cout << "Rank #" << (i + 1) << ": " << scores.at(i) << std::endl;

}

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]

🛠️ Execution Output:

⊞Command Execution Snippet

--- Sorted Student Scores (Total: 7) ---

Rank #1: 72

Rank #2: 84

Rank #3: 88

Rank #4: 91

Rank #5: 95

Rank #6: 99

Rank #7: 100