C++ STL入门教程(3) deque双向队列使用方法

/*请务必运行以下程序后对照阅读*/ 
 
#include <deque> 
#include <iostream> 
#include <algorithm> 
#include <stdexcept> 
using namespace std; 
 
void print(int num) 
{ 
  cout << num << " "; 
} 
 
int main() 
{ 
  //1. 初始化 
  deque<int> v; 
  deque<int>::iterator iv; 
 
  v.assign(10, 2);//将10个值为2的元素赋到deque中 
  cout << v.size() << endl; //返回deque实际含有的元素数量 
  cout << endl; 
 
  //2. 添加 
  v.push_front(666); 
  for (int i = 0; i < 10; i++) 
    v.push_back(i); 
  for_each(v.begin(), v.end(), print);//需要#include <algorithm> 
  cout << endl; 
  cout << v.size() << endl; 
  cout << endl; 
 
  //3. 插入及遍历、逆遍历 
  v.insert(v.begin() + 3, 99); 
  v.insert(v.end() - 3, 99); 
  for_each(v.begin(), v.end(), print); 
  cout << endl; 
  for_each(v.rbegin(), v.rend(), print);//在逆序迭代器上做++运算将指向容器中的前一个元素 
  cout << endl; 
 
  //一般遍历写法 
  for(iv = v.begin(); iv != v.end(); ++iv) 
    cout << *iv << " "; 
  cout << endl; 
  cout << endl; 
 
  //4. 删除 
  v.erase(v.begin() + 3); 
  for_each(v.begin(), v.end(), print); 
  cout << endl; 
  v.insert(v.begin() + 3, 99);//还原 
 
  v.erase(v.begin(), v.begin() + 3); //注意删除了3个元素而不是4个 
  for_each(v.begin(), v.end(), print); 
  cout << endl; 
 
  v.pop_front(); 
  v.pop_back(); 
  for_each(v.begin(), v.end(), print); 
  cout << endl; 
  cout << endl; 
 
  //5. 查询 
  cout << v.front() << endl; 
  cout << v.back() << endl; 
 
  //危险的做法，但一般我们就像访问数组那样操作就行 
  for (int i = 15; i < 25; i++) 
    cout << "Element " << i << " is " << v[i] << endl; 
  //安全的做法 
  int i; 
  try 
  { 
    for (i = 15; i < 25; i++) 
      cout << "Element " << i << " is " << v.at(i) << endl; 
  } 
  catch (out_of_range err)//#include <stdexcept> 
  { 
    cout << "out_of_range at " << i << endl; 
  } 
  cout << endl; 
 
  //6. 清空 
  v.clear(); 
  cout << v.size() << endl;//0 
  for_each(v.begin(), v.end(), print); //已经clear，v.begin()==v.end()，不会有任何结果。 
 
  return 0; 
}