Vectors [cpp}

Vectors
You can think of vectors as smart arrays. They manage storage allocation for you, expanding
and contracting the size of the vector as you insert or erase data. You can use vectors much like
arrays, accessing elements with the [] operator. Such random access is very fast with vectors.

It’s also fast to add (or push) a new data item onto the end (the back) of the vector. When this
happens, the vector’s size is automatically increased to hold the new item.
Member Functions push_back(), size(), and operator[]
Our first example, VECTOR, shows the most common vector operations.
// vector.cpp
// demonstrates push_back(), operator[], size()
#include <iostream>
#include <vector>
using namespace std;
int main()
{
vector<int> v; //create a vector of ints
v.push_back(10); //put values at end of array
v.push_back(11);
v.push_back(12);
v.push_back(13);
v[0] = 20; //replace with new values
v[3] = 23;
for(int j=0; j<v.size(); j++) //display vector contents
cout << v[j] << ‘ ‘; //20 11 12 23
cout << endl;
return 0;
}