Vectors in C++ are dynamic arrays provided by the Standard Template Library (STL). Unlike normal arrays, vectors can automatically grow or shrink in size during program execution.<\/p>\n\n\n\n
A vector is a sequence container that stores elements like an array but provides dynamic resizing and many useful built-in functions.<\/p>\n\n\n\n
Vectors are useful because they:<\/p>\n\n\n\n
To use vectors in C++, include the This creates an empty vector of integers.<\/p>\n\n\n\n Elements can be accessed using indexing.<\/p>\n\n\n\n Modern C++ supports range-based loops.<\/p>\n\n\n\n Vectors support iterators for traversal.<\/p>\n\n\n\n Think of a shopping cart:<\/p>\n\n\n\n This is similar to how vectors work.<\/p>\n\n\n\n Vectors are widely used in:<\/p>\n\n\n\n Vectors are important because they:<\/p>\n\n\n\n Vectors in C++ are powerful dynamic containers that automatically manage memory and resize during runtime. With built-in STL functions and flexible operations, vectors are widely used in modern C++ programming for efficient and scalable applications.<\/p>\n\n\n<vector><\/code> library.<\/p>\n\n\n\n#include <vector><\/code><\/pre>\n\n\n\nDeclaring a Vector<\/h1>\n\n\n\n
vector<int> numbers;<\/code><\/pre>\n\n\n\nInitializing a Vector<\/h1>\n\n\n\n
vector<int> numbers = {10, 20, 30, 40};<\/code><\/pre>\n\n\n\nAdding Elements Using push_back()<\/h1>\n\n\n\n
push_back()<\/code> adds elements at the end of the vector.<\/p>\n\n\n\nExample<\/h2>\n\n\n\n
numbers.push_back(50);<\/code><\/pre>\n\n\n\nAccessing Vector Elements<\/h1>\n\n\n\n
Example<\/h2>\n\n\n\n
cout << numbers[0];
cout << numbers.at(1);<\/code><\/pre>\n\n\n\nExample Program of Vector<\/h1>\n\n\n\n
#include <iostream>
#include <vector>
using namespace std;
int main() {
vector<int> numbers = {1, 2, 3};
numbers.push_back(4);
for (int i = 0; i < numbers.size(); i++) {
cout << numbers[i] << endl;
}
return 0;
}<\/code><\/pre>\n\n\n\nOutput<\/h2>\n\n\n\n
1
2
3
4<\/code><\/pre>\n\n\n\nCommon Vector Functions<\/h1>\n\n\n\n
Function<\/th> Purpose<\/th><\/tr><\/thead> push_back()<\/code><\/td>Add element at end<\/td><\/tr> pop_back()<\/code><\/td>Remove last element<\/td><\/tr> size()<\/code><\/td>Get number of elements<\/td><\/tr> clear()<\/code><\/td>Remove all elements<\/td><\/tr> empty()<\/code><\/td>Check if vector is empty<\/td><\/tr> at()<\/code><\/td>Access element safely<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Example of Vector Functions<\/h1>\n\n\n\n
#include <iostream>
#include <vector>
using namespace std;
int main() {
vector<int> numbers = {10, 20, 30};
numbers.pop_back();
cout << numbers.size();
return 0;
}<\/code><\/pre>\n\n\n\nOutput<\/h2>\n\n\n\n
2<\/code><\/pre>\n\n\n\nUsing Range-Based Loop with Vector<\/h1>\n\n\n\n
Example<\/h2>\n\n\n\n
#include <iostream>
#include <vector>
using namespace std;
int main() {
vector<int> numbers = {5, 10, 15};
for (int num : numbers) {
cout << num << endl;
}
return 0;
}<\/code><\/pre>\n\n\n\nOutput<\/h2>\n\n\n\n
5
10
15<\/code><\/pre>\n\n\n\nVector Iterators<\/h1>\n\n\n\n
Example<\/h2>\n\n\n\n
#include <iostream>
#include <vector>
using namespace std;
int main() {
vector<int> v = {1, 2, 3};
for (auto it = v.begin(); it != v.end(); it++) {
cout << *it << endl;
}
return 0;
}<\/code><\/pre>\n\n\n\nDifference Between Arrays and Vectors<\/h1>\n\n\n\n
Arrays<\/th> Vectors<\/th><\/tr><\/thead> Fixed size<\/td> Dynamic size<\/td><\/tr> Manual memory handling<\/td> Automatic memory management<\/td><\/tr> Limited functions<\/td> Many built-in functions<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n Important Points About Vectors<\/h1>\n\n\n\n
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Advantages of Vectors<\/h1>\n\n\n\n
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Common Mistakes with Vectors<\/h1>\n\n\n\n
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size()<\/code> with capacity<\/li>\n<\/ul>\n\n\n\nReal-Life Example<\/h1>\n\n\n\n
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Applications of Vectors<\/h1>\n\n\n\n
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Why Vectors are Important<\/h1>\n\n\n\n
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Conclusion<\/h2>\n\n\n\n