Quick Answer

Master the std::vector container.

Understanding the Issue

Vectors are dynamic arrays that provide random access and automatic resizing. They are the most commonly used STL container.

The Problem

This code demonstrates the issue:

Cpp Error 
// Need a resizable array of integers

The Solution

Here's the corrected code:

Cpp Fixed 
#include <vector>
#include <algorithm>

int main() {
    // Create and populate
    std::vector<int> numbers = {7, 3, 5, 1};
    
    // Add elements
    numbers.push_back(9);
    
    // Access elements
    int first = numbers[0];
    int last = numbers.back();
    
    // Sort
    std::sort(numbers.begin(), numbers.end());
    
    // Range-based for loop (C++11)
    for (int num : numbers) {
        std::cout << num << " ";
    }
    // Output: 1 3 5 7 9
    
    return 0;
}

Key Takeaways

Vectors combine array performance with dynamic resizing.