set查找

#include <iostream>
#include <set>
#include <algorithm>
using namespace std;

class Print
{
public:
   void operator()(int i)
   {
      cout << i << endl;
   }
};

int main()
{
   set<int> s;
   s.insert(1);
   s.insert(3);
   s.insert(2);

   for_each(s.begin(), s.end(), Print());

   set<int>::iterator it = s.find(3);
   if(it != s.end())
   {
      cout << "找到 " << *it << endl;
   }
   else
   {
      cout << "未找到" << endl;
   }


   return 0;
}

$ ./a.out 
1
2
3
找到 3