#include <iostream>
#include <vector>using namespace std;
const int NUM = 5;int main()
{vector<int> ratings(NUM);int i;for(i=0; i<NUM; i++)cin>>ratings[i];for(i=0; i<NUM; i++)cout<<ratings[i]<<"\n";
　　 cout<<"4th: "<<ratings[3]<<endl;return 0;
}

vector<double> test;
double temp;
while(cin >> temp && temp >=0)
{test.push_back(temp);
}
test.erase(test.begin(), test.begin() + 10); //如果容器的元素总数不足10个，则会发生地址错误
cout<<"you entered "<<test.size()<<" elements.\n";//这时的元素总数在上一步被减去了10个

#include <iostream>
#include <string>
#include <vector>
#include <algorithm>using namespace std;struct Review {string title;int rating;
};bool operator<(const Review &r1, const Review &r2);
bool worseThan(const Review &r1, const Review &r2);
bool FillReview(Review &rr);
void ShowReview(const Review &rr);int main()
{vector<Review> books;Review temp;while(FillReview(temp))books.push_back(temp);if(books.size() > 0){cout<<"size: "<<books.size()<<" ratings:\nrating\tbook\n";for_each(books.begin(), books.end(), ShowReview);sort(books.begin(), books.end());cout<<"sort by title: \n rating\tbook\n";for_each(books.begin(), books.end(), ShowReview);sort(books.begin(), books.end(), worseThan);cout<<"sort by rating: \n rating\tbook\n";for_each(books.begin(), books.end(), ShowReview);random_shuffle(books.begin(), books.end());cout<<"sort shuffle: \n rating\tbook\n";for_each(books.begin(), books.end(), ShowReview);random_shuffle(books.begin(), books.end());cout<<"sort shuffle2: \n rating\tbook\n";for_each(books.begin(), books.end(), ShowReview);}elsecout<<"No enteris. ";cout<<"Bye. \n";return 0;
}bool operator<(const Review &r1, const Review &r2)
{if(r1.title < r2.title)return true;else if(r1.title == r2.title && r1.rating < r2.rating)return true;elsereturn false;
}bool worseThan(const Review &r1, const Review &r2)
{if(r1.rating < r2.rating)return true;elsereturn false;
}bool FillReview(Review &rr)
{cout<<"enter book title: ";getline(cin, rr.title);if(rr.title == "q")return false;cout<<"enter book rating: ";cin>>rr.rating;if(!cin)return false;while(cin.get() != '\n')continue;return true;
}void ShowReview(const Review &rr)
{cout<<rr.rating<<"\t"<<rr.title<<endl;
}

#include <iostream>
#include <string>
#include <set>
#include <algorithm>
#include <iterator>int main()
{using namespace std;const int N = 6;string s1[N] = {"atest","aetst","aestt","aetts","atset","atets"};string s2[N] = {"bingy","bany","bfood","belegant","bdeliver","bfor"};set<string> A(s1, s1+N);set<string> B(s2, s2+N);ostream_iterator<string, char> out(cout, " ");cout<<"Set A";copy(A.begin(), A.end(), out);cout<<endl;cout<<"Set B";copy(B.begin(), B.end(), out);cout<<endl;cout<<"Union of A and B:\n";set_union(A.begin(), A.end(), B.begin(), B.end(), out);cout<<endl;cout<<"Intersection of A and B:\n";set_intersection(A.begin(), A.end(), B.begin(), B.end(), out);cout<<endl;cout<<"Difference of A and B:\n";set_difference(A.begin(), A.end(), B.begin(), B.end(), out);cout<<endl;set<string> C;cout<<"Set C:\n";set_union(A.begin(), A.end(), B.begin(), B.end(), insert_iterator<set<string> > (C, C.begin()));copy(C.begin(), C.end(), out);cout<<endl;string s3("grungy");C.insert(s3);cout<<"Set C after insertion:\n";copy(C.begin(), C.end(), out);cout<<endl;copy(C.lower_bound("ghost"),C.upper_bound("spook"), out);cout<<endl;return 0;
}

//array
double *find(double *a, int n, double &val)
{for(int i=0; i<n; ++i){if(val == ar[i]){return &ar[i]; //
        }}return 0; //C++11: return nullptr;
}//linklist
Node *find(Node *head, const double &val)
{Node *ret=head;while(ret!=0){if(ret->data == data)return ret;ret=ret->next;}return 0;
}//STL iterator for array
typedef double* iterator;
iterator find_it(iterator it, int n, const double &val)
{int i=0;while(i<n){if(*it == val)return it;i++;it++;}return 0;
}//STL iterator for array II
typedef double* iterator;
iterator find_it(iterator begin, iterator end, const double &val)
{iterator it=begin;while(it!=end){if(*it == val)return it;it++;}return end;
}//STL iterator for LinkList
struct Node {double data;Node *next;
};class iterator {
private:Node *node_;
public:iterator() : node_(0) {}iterator(Node *node) : node_(node) {}double operator*() { return node_->data; }iterator &operator++(){node_ = node_->next;return *this;}iterator operator++(int){iterator tmp = *this;node_ = node_->next;return tmp;}
};iterator find_it(iterator begin, const double &val)
{iterator it=begin;while(it!=0){if(*it == val)return it;it++;}return 0;
}