STL中的set集合容器进行集合运算：并、交、差实例

集合容器的集合运算：并、交、差：

#include
"stdafx.h"
#include
<iostream>
#include
<set>
#include
<algorithm> //集合运算：并、交、差需要包含该头文件
using namespace std;
structltstr
{
    bool
operator()(const
char* s1,const char* s2)
const
    {
       return strcmp(s1,s2)<0; //由小到大排序
//return strcmp(s1,s2)<0; //由大到小排序
    }
};

int_tmain(int argc, _TCHAR* argv[])
{

const int N = 6;
    const
char* a
= {"isomer","ephemeral","prosaic","nugatory","artichoke","serif"};
    const
char* b
= {"flat","this","artichoke","frigate","prosaic","isomer"};
    set<const
char*,ltstr>A(a,a+N);
    set<const
char*,ltstr> B(b,b+N);
    set<const
char*,ltstr>C;
    set<const
char*,ltstr>D;
    cout<<"Set A:";
    copy(A.begin(),A.end(),ostream_iterator<const
char*>(cout," "));
    cout<<endl;
    cout<<"Set B:";
    copy(B.begin(),B.end(),ostream_iterator<const
char*>(cout," "));
    cout<<endl;
    cout<<"Union: ";
    //set_union函数需要#include <algorithm>
    set_union(A.begin(),A.end(),B.begin(),B.end(),ostream_iterator<const
char*>(cout," "),ltstr());
    cout<<endl;
    cout<<"Intersection: ";
    set_intersection(A.begin(),A.end(),B.begin(),B.end(),ostream_iterator<const
char*>(cout," "),ltstr());
    cout<<endl;
    cout<<"Set C (difference of A and B):";
    set_difference(A.begin(),A.end(),B.begin(),B.end(),inserter(C,C.begin()),ltstr());//从A中减去B包含的元素
    copy(C.begin(),C.end(),ostream_iterator<const
char*>(cout," "));
    cout<<endl;
    cout<<"Set D (difference of B and A):";
    set_difference(B.begin(),B.end(),A.begin(),A.end(),inserter(D,D.begin()),ltstr());//从B中减去A包含的元素
    copy(D.begin(),D.end(),ostream_iterator<const
char*>(cout," "));
    cout<<endl;
    return 0;

}

运行结果：