C++ Tutorial/vector/vector begin end

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Assign elements in vector a value through an iterator

#include <iostream>
#include <vector>
#include <cctype>
using namespace std;
int main()
{
  vector<char> v(10); // create a vector of length 10
  vector<char>::iterator p; // create an iterator
  int i;
  // assign elements in vector a value
  p = v.begin();
  i = 0;
  while(p != v.end()) {
    *p = i + "a";
    p++;
    i++;
  }

  return 0;
}

Delete the first element of the vector

#include <iostream>
#include <vector>
using namespace std;
typedef vector<int> INTVECTOR;
const int ARRAY_SIZE = 4;
int main(void)
{
   INTVECTOR theVector;
   // Intialize the array to contain the members [100, 200, 300, 400]
   for (int cEachItem = 0; cEachItem < ARRAY_SIZE; cEachItem++)
      theVector.push_back((cEachItem + 1) * 100);
   cout << "First element: " << theVector.front() << endl;
   cout << "Last element: " << theVector.back() << endl;
   cout << "Elements in vector: " << theVector.size() << endl;
   // Delete the first element of the vector.
   theVector.erase(theVector.begin());
   cout << "New first element is: " << theVector.front() << endl;
   cout << "Elements in vector: " << theVector.size() << endl;
}

Delete the last element of the vector

#include <iostream>
#include <vector>
using namespace std;
typedef vector<int> INTVECTOR;
const int ARRAY_SIZE = 4;
int main(void)
{
   INTVECTOR theVector;
   // Intialize the array to contain the members [100, 200, 300, 400]
   for (int cEachItem = 0; cEachItem < ARRAY_SIZE; cEachItem++)
      theVector.push_back((cEachItem + 1) * 100);
   cout << "First element: " << theVector.front() << endl;
   cout << "Last element: " << theVector.back() << endl;
   cout << "Elements in vector: " << theVector.size() << endl;
   cout << "Deleting last element." << endl;
   theVector.erase(theVector.end() - 1);
   cout << "New last element is: " << theVector.back() << endl;
}

Get the last element in a vector

#include <iostream>
#include <vector>
using namespace std;
typedef vector<int> INTVECTOR;
const int ARRAY_SIZE = 4;
int main(void)
{
   INTVECTOR theVector;
   // Intialize the array to contain the members [100, 200, 300, 400]
   for (int cEachItem = 0; cEachItem < ARRAY_SIZE; cEachItem++)
      theVector.push_back((cEachItem + 1) * 100);
   cout << "Last element: " << theVector.back() << endl;
}
Источник — «http://cppe.ru/index.php?title=C%2B%2B_Tutorial/vector/vector_begin_end&oldid=2206»