deque: constructor, size(), push_back(), pop_back(), begin(), end() : deque pop « deque « C++ Tutorial

1. C++ Tutorial
2. deque
3. deque pop

#include <iostream>
#include <deque>

using namespace std;

void show(const char *msg, deque<int> q);

int main() {

  deque<int> dq(10);

  for(unsigned i=0; i < dq.size(); ++i) dq[i] = i*i;

  show("Contents of dq: ", dq);

  int sum = 0;
  for(unsigned i=0; i < dq.size(); ++i) sum += dq[i];
  double avg = sum / dq.size();
  cout << avg << endl;

  // Add elements to the end of dq.
  dq.push_back(100);
  dq.push_back(121);

  show("dq after pushing elements onto the end: ", dq);

  // Now use pop_back() to remove one element.
  dq.pop_back();
  show("dq after back-popping one element: ", dq);

  cout << *dq.begin() << ", " << *(dq.end()-1) << "\n\n";

  cout << *dq.rbegin() << ", " << *(dq.rend()-1) << "\n\n";

  return 0;
}
// Display the contents of a deque<int>.
void show(const char *msg, deque<int> q) {
  cout << msg;
  for(unsigned i=0; i < q.size(); ++i)
    cout << q[i] << " ";
  cout << "\n";
}