vectorinsertanderase.cpp

C++编程思想第二版第一册答案

//: C20:VectorInsertAndErase.cpp
// From Thinking in C++, 2nd Edition
// Available at http://www.BruceEckel.com
// (c) Bruce Eckel 1999
// Copyright notice in Copyright.txt
// Erasing an element from a vector
#include "Noisy.h"
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
  vector<Noisy> v;
  v.reserve(11);
  cout << "11 spaces have been reserved" << endl;
  generate_n(back_inserter(v), 10, NoisyGen());
  ostream_iterator<Noisy> out(cout, " ");
  cout << endl;
  copy(v.begin(), v.end(), out);
  cout << "Inserting an element:" << endl;
  vector<Noisy>::iterator it = 
    v.begin() + v.size() / 2; // Middle
  v.insert(it, Noisy());
  cout << endl;
  copy(v.begin(), v.end(), out);
  cout << "\nErasing an element:" << endl;
  // Cannot use the previous value of it:
  it = v.begin() + v.size() / 2;
  v.erase(it);
  cout << endl;
  copy(v.begin(), v.end(), out);
  cout << endl;
} ///:~