C++ 算法 中的 generate函数

template <class ForwardIterator, class Generator>
  void generate (ForwardIterator first, ForwardIterator last, Generator gen);

#include <algorithm>
#include <iostream>
#include <vector>

using namespace std;

int main() {
  vector<int> v(10);

  int n = 1;
  generate(v.begin(), v.end(), [&n]() { 
      auto t = n; 
      n *= 2; 
      return t; 
      } );

  for_each(v.begin(), v.end(), [](int x) { 
      cout << x << ","; 
      });
  
  return 0;
}

#include <iostream> 
#include <vector> 
#include <algorithm> 
  
// Defining the generator function 
int gen() 
{ 
    static int i = 0; 
    return ++i; 
} 
  
using namespace std; 
int main() 
{ 
    int i; 
  
   //Declaring a vector of size 10 
    vector<int> v1(10); 
  
   //using std::generate 
    std::generate(v1.begin(), v1.end(), gen); 
  
    vector<int>::iterator i1; 
    for (i1 = v1.begin(); i1 != v1.end(); ++i1) { 
        cout << *i1 << " "; 
    } 
    return 0; 
}

#include <vector>  
#include <deque>  
#include <algorithm>  
#include <iostream>  
#include <ostream>  
  
int main( )  
{  
   using namespace std;  
  
  //Assigning random values to vector integer elements  
   vector <int> v1 ( 5 );  
   vector <int>::iterator Iter1;  
   deque <int> deq1 ( 5 );  
   deque <int>::iterator d1_Iter;  
  
   generate ( v1.begin ( ), v1.end ( ) , rand );  
  
   cout << "Vector v1 is ( " ;  
   for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )  
      cout << *Iter1 << " ";  
   cout << ")." << endl;  
  
  //Assigning random values to deque integer elements  
   generate ( deq1.begin ( ), deq1.end ( ) , rand );  
  
   cout << "Deque deq1 is ( " ;  
   for ( d1_Iter = deq1.begin( ) ; d1_Iter != deq1.end( ) ; d1_Iter++ )  
      cout << *d1_Iter << " ";  
   cout << ")." << endl;  
   
   return 0;
}

#include <iostream>    //std::cout
#include <algorithm>   //std::generate
#include <vector>      //std::vector
#include <ctime>       //std::time
#include <cstdlib>     //std::rand, std::srand

using namespace std;

// function generator:
int RandomNumber () { return (rand()%100); }

// class generator:
struct c_unique {
  int current;
  c_unique() {current=0;}
  int operator()() {return ++current;}
} UniqueNumber;

int main () {
  srand ( unsigned ( std::time(0) ) );

  vector<int> myvector (8);

  generate (myvector.begin(), myvector.end(), RandomNumber);

  cout << "myvector contains:";
  for (vector<int>::iterator it=myvector.begin(); it!=myvector.end(); ++it)
    cout << ' ' << *it;
  cout << '\n';

  generate (myvector.begin(), myvector.end(), UniqueNumber);

  cout << "myvector contains:";
  for (vector<int>::iterator it=myvector.begin(); it!=myvector.end(); ++it)
    cout << ' ' << *it;
   cout << '\n';
 
  return 0;
}