msdn bind2nd函数示例

Question

我在Windows 7 64位上使用MS VS 6.0和SP 6。Win32控制台应用程序。仍然使用VS6.0，因为我必须维护遗留代码。大多数VS6的工作都没有问题。

我试图通过查看：https://msdn.microsoft.com/en-us/library/3f0defz2.aspx来了解bind2nd

编译时代码失败，出现错误(其中包括)：error C2955：'iterator‘：使用类模板需要模板参数列表代码在下面注释后的行上失败

我如何纠正这段代码，使其能够编译？

代码是

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

using namespace std; 

// Creation of a user-defined function object that inherits from 
// the unary_function base class 
class greaterthan15: unary_function<int, bool> 
{ 
public: 
    result_type operator()( argument_type i ) 
    { 
        return ( result_type )( i > 15 ); 
    } 
}; 

int main() 
{ 
    vector<int> v1; 
    vector<int>::iterator Iter; 

    int i; 
    for ( i = 0; i <= 5; i++ ) 
    { 
        v1.push_back( 5 * i ); 
    } 

    cout << "The vector v1 = ( "; 
    for ( Iter = v1.begin(); Iter != v1.end(); Iter++ ) 
        cout << *Iter << " "; 
    cout << ")" << endl; 

    // Count the number of integers > 10 in the vector 
    // COMPILE FAILS ON NEXT LINE 
    vector<int>::iterator::difference_type result1a; 
    result1a = count_if( v1.begin(), v1.end(), bind2nd( greater<int>(), 10 ) ); 
    cout << "The number of elements in v1 greater than 10 is: " 
        << result1a << "." << endl; 

    // Compare counting the number of integers > 15 in the vector with 
    // a user-defined function object 
    vector<int>::iterator::difference_type result1b; 
    result1b = count_if( v1.begin(), v1.end(), greaterthan15() ); 
    cout << "The number of elements in v1 greater than 15 is: " 
        << result1b << "." << endl; 

    // Count the number of integers < 10 in the vector 
    vector<int>::iterator::difference_type result2; 
    result2 = count_if( v1.begin(), v1.end(), bind1st(greater<int>(), 10 ) ); 
    cout << "The number of elements in v1 less than 10 is: " 
        << result2 << "." << endl; 

} 

Answer 1

我处于幸运的位置，不用再使用MSVC6，所以我不能检查我的建议，不管怎样，试着转向

vector<int>::iterator::difference_type

转到

vector<int>::difference_type