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先來看看如何賦值把:
#include <iostream>
#include <vector>
#include <string>
#include<deque>
#include <set>
#include <map>
#include <boost/assign.hpp>
using namespace std;
int _tmain(int argc, _TCHAR* argv[])
{
using namespace boost::assign;
//使用list_of
vector<int> v=list_of(1)(2)(3)(4)(5);
deque<string>d=(list_of("hello")("rollen"));
set<int>s=(list_of(10),20,30,40);
map<int, string>m=list_of(make_pair(1,"hello"))(make_pair(2,"rollen"));
//list_of可以全部使用括號,也可以將括號和逗號一起使用,但是對于后者需要
// 將整個lits_of用括號括起來。否則編譯器無法推導(dǎo)出list_of的類型而無法賦值。
// 下面使用map_list_of 和pair_list_of
map<int,int>mp=map_list_of(1,1)(2,2)(3,3);
map<int,string>mp2=pair_list_of(1,"hello")(2,"rollen");
//其實還有tuple_list_of
}
#include <iostream>
#include <vector>
#include <string>
#include<deque>
#include <set>
#include <map>
#include <multiset>
#include <boost/assign.hpp>
using namespace std;
//減少重復(fù)輸入
int _tmain(int argc, _TCHAR* argv[])
{
using namespace boost::assign;
vector<int>v=list_of(1).repeat(2,3)(4)(5); //將3重復(fù)2次
//v=1,3,3,4,5
multiset<int>ms;
insert(ms).repeat_fun(5,&rand).repeat(2,1),10;
//ms=x,x,x,x,x,1,1,10
deque<int>d;
push_front(d).range(v.begin(),v.end()); //將一個序列的元素插入另外一個序列
//d=1,3,3,4,5
}
與非標(biāo)準(zhǔn)容器一起使用
#include <iostream>
#include <vector>
#include <string>
#include <stack>
#include <queue>
#include <boost/assign.hpp>
using namespace std;
//與非標(biāo)準(zhǔn)容器一起使用
int _tmain(int argc, _TCHAR* argv[])
{
using namespace boost::assign;
stack<int>s=(list_of(1),2,3).to_adapter();
while(!s.empty()){
cout<<s.top()<<" ";
s.pop();
}
cout<<endl;
queue<string>q=(list_of("hello")("rollen").repeat(2,"holt")).to_adapter();
while(!q.empty()){
cout<<q.front()<<" ";
q.pop();
}
cout<<endl;
priority_queue<double>pq=(list_of(1.21)(2.23)).to_adapter();
while(!pq.empty()){
cout<<pq.top()<<" ";
pq.pop();
}
cout<<endl;
}
assign也支持部分不在STL中定義的非標(biāo)準(zhǔn)容器,比如slist和hash_map hash_set 用法和標(biāo)準(zhǔn)容器一樣、 此外,assign也支持大部分Boost的庫容器
#include <iostream>
#include <vector>
#include <string>
#include <boost/assign.hpp>
using namespace std;
//list_of的嵌套使用
// 構(gòu)建二維數(shù)組
int _tmain(int argc, _TCHAR* argv[])
{
using namespace boost::assign;
vector<vector<int> >v=list_of(list_of(1)(2))(list_of(3)(4));
v+=list_of(5)(6),list_of(7)(8);
int a=1,b=2,c=3;
vector<int>v1=cref_list_of<3>(a)(b)(c); //也可以使用ref_list_of
assert(v.size()==3);
}
#include <boost/swap.hpp>
using namespace std;
//交換兩個數(shù)組,兩個數(shù)組的長度必須一致
int _tmain(int argc, _TCHAR* argv[])
{
int a1[10];
int a2[10];
std::fill_n(a1,10,1);
std::fill_n(a2,10,2);
boost::swap(a1,a2);
}
特化 swap
#include <iostream>
#include <vector>
#include <string>
#include <boost/swap.hpp>
using namespace std;
class point{
public:
explicit point(int a,int b,int c):x(a),y(b),z(c){}
void print()const{
cout<<x<<" "<<y<<" "<<z<<endl;
}
void swap(point &p){
std::swap(x,p.x);
std::swap(y,p.y);
std::swap(z,p.z);
cout<<"inner swap"<<endl;
}
private:
int x,y,z;
};
//特化std::swap 原則上不能動std
namespace std{
template<>
void swap(point &x,point &y){
x.swap(y);
}
}
int _tmain(int argc, _TCHAR* argv[])
{
point a(1,2,3);
point b(4,5,6);
cout<<"std swap"<<endl;
std::swap(a,b);
cout<<"boost swap"<<endl;
boost::swap(a,b);
}
由于我們特化了swap,因此boost::swap 和std::swap效果一樣 特化ADL可找到的swap
#include <iostream>
#include <vector>
#include <string>
#include <boost/swap.hpp>
using namespace std;
class point{
public:
explicit point(int a,int b,int c):x(a),y(b),z(c){}
void print()const{
cout<<x<<" "<<y<<" "<<z<<endl;
}
void swap(point &p){
std::swap(x,p.x);
std::swap(y,p.y);
std::swap(z,p.z);
cout<<"inner swap"<<endl;
}
private:
int x,y,z;
};
void swap(point &x,point &y){
x.swap(y);
}
int _tmain(int argc, _TCHAR* argv[])
{
point a(1,2,3);
point b(4,5,6);
cout<<"std swap"<<endl;
std::swap(a,b);
cout<<"boost swap"<<endl;
boost::swap(a,b);
}
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