min

比较两个对象并返回两个中小的，其中是排序的标准可以由二进制谓词指定。

template<class Type>
    const Type& min(
        const Type& _Left, 
        const Type& _Right
    );
template<class Type, class Pr>
    const Type& min(
        const Type& _Left, 
        const Type& _Right,
        BinaryPredicate _Comp
    );
template<class Type> 
    Type min ( initializer_list<Type> _Ilist
    );
template<class Type, class Pr>
    Type min (
        initializer_list<Type> _Ilist, 
        BinaryPredicate _Comp
    );

参数

• _Left
  比较的第一个对象。

• _Right
  比较的第二个对象。

• _Comp
  用于比较两个对象的二进制谓词。

• _IList
  包含要比较的成员象的初始值设定项列表。

返回值

两个对象中的小的的，除非，一样大；在这种情况下，它将返回第一个对象。 在 initializer_list中，它将返回列表中的最小对象。

备注

当对象作为参数被传递时，min算法是不寻常的。 大多数标准模板库算法在迭代器指定元素的范围内执行，迭代器由参数传递。 如果您需要使用一些元素，使用max_element。

示例

// alg_min.cpp
// compile with: /EHsc
#include <vector>
#include <set>
#include <algorithm>
#include <iostream>
#include <ostream>

using namespace std;
class CInt;
ostream& operator<<( ostream& osIn, const CInt& rhs );

class CInt
{
public:
    CInt( int n = 0 ) : m_nVal( n ){}
    CInt( const CInt& rhs ) : m_nVal( rhs.m_nVal ){}
    CInt& operator=( const CInt& rhs ) {m_nVal = 
    rhs.m_nVal; return *this;}
    bool operator<( const CInt& rhs ) const 
        {return ( m_nVal < rhs.m_nVal );}
    friend ostream& operator<<(ostream& osIn, const CInt& rhs);

private:
    int m_nVal;
};

inline ostream& operator<<( ostream& osIn, const CInt& rhs )
{
    osIn << "CInt( " << rhs.m_nVal << " )"; 
       return osIn;
}

// Return whether modulus of elem1 is less than modulus of elem2
bool mod_lesser ( int elem1, int elem2 )
{
    if ( elem1 < 0 ) 
        elem1 = - elem1;
    if ( elem2 < 0 ) 
        elem2 = - elem2;
    return elem1 < elem2;
};

int main( )
{
    // Comparing integers directly using the min algorithm with
    // binary predicate mod_lesser & with default less than
    int a = 6, b = -7, c = 7 ;
    const int& result1 = min ( a, b, mod_lesser );
    const int& result2 = min ( b, c );

    cout << "The mod_lesser of the integers 6 & -7 is: " 
        << result1 << "." << endl;
     cout << "The lesser of the integers -7 & 7 is: " 
        << result2 << "." << endl;
    cout << endl;

// Comparing the members of an initializer_list
    const int& result3 = min({ a, c });
    const int& result4 = min({ a, b }, mod_lesser);

    cout << "The lesser of the integers 6 & 7 is: "
        << result3 << "." << endl;
    cout << "The mod_lesser of the integers 6 & -7 is: "
        << result4 << "." << endl;
    cout << endl;

    // Comparing set containers with elements of type CInt 
       // using the min algorithm
    CInt c1 = 1, c2 = 2, c3 = 3;
    set<CInt> s1, s2, s3;
    set<CInt>::iterator s1_Iter, s2_Iter, s3_Iter;
   
    s1.insert ( c1 );
    s1.insert ( c2 );
    s2.insert ( c2 );
    s2.insert ( c3 );

    cout << "s1 = (";
    for ( s1_Iter = s1.begin( ); s1_Iter != --s1.end( ); s1_Iter++ )
        cout << " " << *s1_Iter << ",";
    s1_Iter = --s1.end( );
        cout << " " << *s1_Iter << " )." << endl;

    cout << "s2 = (";
    for ( s2_Iter = s2.begin( ); s2_Iter != --s2.end( ); s2_Iter++ )
        cout << " " << *s2_Iter << ",";
    s2_Iter = --s2.end( );
    cout << " " << *s2_Iter << " )." << endl;

    s3 = min ( s1, s2 );
    cout << "s3 = min ( s1, s2 ) = (";
    for ( s3_Iter = s3.begin( ); s3_Iter != --s3.end( ); s3_Iter++ )
        cout << " " << *s3_Iter << ",";
    s3_Iter = --s3.end( );
    cout << " " << *s3_Iter << " )." << endl << endl;

    // Comparing vectors with integer elements using min algorithm
    vector <int> v1, v2, v3, v4, v5;
    vector <int>::iterator Iter1, Iter2, Iter3, Iter4, Iter5;

    int i;
    for ( i = 0 ; i <= 2 ; i++ )
    {
        v1.push_back( i );
    }

    int ii;
    for ( ii = 0 ; ii <= 2 ; ii++ )
    {
        v2.push_back( ii );
    }

    int iii;
    for ( iii = 0 ; iii <= 2 ; iii++ )
    {
        v3.push_back( 2 * iii );
    }
   
    cout << "Vector v1 is ( " ;
    for ( Iter1 = v1.begin( ) ; Iter1 != v1.end( ) ; Iter1++ )
        cout << *Iter1 << " ";
    cout << ")." << endl;

    cout << "Vector v2 is ( " ;
    for ( Iter2 = v2.begin( ) ; Iter2 != v2.end( ) ; Iter2++ )
        cout << *Iter2 << " ";
    cout << ")." << endl;
   
    cout << "Vector v3 is ( " ;
    for ( Iter3 = v3.begin( ) ; Iter3 != v3.end( ) ; Iter3++ )
        cout << *Iter3 << " ";
    cout << ")." << endl;

    v4 = min ( v1, v2 );
    v5 = min ( v1, v3 );

    cout << "Vector v4 = min ( v1,v2 ) is ( " ;
    for ( Iter4 = v4.begin( ) ; Iter4 != v4.end( ) ; Iter4++ )
        cout << *Iter4 << " ";
    cout << ")." << endl;

    cout << "Vector v5 = min ( v1,v3 ) is ( " ;
    for ( Iter5 = v5.begin( ) ; Iter5 != v5.end( ) ; Iter5++ )
        cout << *Iter5 << " ";
    cout << ")." << endl;
}

要求

标头： <算法>

命名空间: std

请参见

参考

标准模板库