example2_resizing_reserve.cpp

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#include <iostream>
#include <vector>

int main() {
    std::vector<int> vec;

    // Reserve space for 10 elements
    vec.reserve(10);
    std::cout << "Size: " << vec.size() << ", Capacity: " << vec.capacity() << std::endl;

    // Add 5 elements
    for (int i = 0; i < 5; ++i) {
        vec.push_back(i);
    }
    std::cout << "Size: " << vec.size() << ", Capacity: " << vec.capacity() << std::endl;

    // Resize to 7 elements
    vec.resize(7);
    std::cout << "Size: " << vec.size() << ", Capacity: " << vec.capacity() << std::endl;

    // Shrink to fit
    vec.shrink_to_fit();
    std::cout << "Size: " << vec.size() << ", Capacity: " << vec.capacity() << std::endl;

    return 0;
}