/*請務必運行以下程序后對照閱讀*/  #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);//將10個值為2的元素賦到deque中   cout << v.size() << endl; //返回deque實際含有的元素數量   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. 插入及遍歷、逆遍歷   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++運算將指向容器中的前一個元素   cout << endl;    //一般遍歷寫法   for(iv = v.begin(); iv != v.end(); ++iv)     cout << *iv << " ";   cout << endl;   cout << endl;    //4. 刪除   v.erase(v.begin() + 3);   for_each(v.begin(), v.end(), print);   cout << endl;   v.insert(v.begin() + 3, 99);//還原    v.erase(v.begin(), v.begin() + 3); //注意刪除了3個元素而不是4個   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. 查詢   cout << v.front() << endl;   cout << v.back() << endl;    //危險的做法，但一般我們就像訪問數組那樣操作就行   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); //已經clear，v.begin()==v.end()，不會有任何結果。    return 0; }