max
命令の条件にバイナリ述語によって指定される可能性がある場合は、2 種類のオブジェクトを比較し、2 より大きい) を返します。
template<class Type>
const Type& max(
const Type& _Left,
const Type& _Right
);
template<class Type, class Pr>
const Type& max(
const Type& _Left,
const Type& _Right,
BinaryPredicate _Comp
);
パラメーター
_Left
比較する 2 種類のオブジェクトの狭い。_Right
比較する 2 種類のオブジェクトの 2 番。_Comp
2 種類のオブジェクトを比較するために使用できるバイナリの述語。
戻り値
2 種類のオブジェクトの先頭が返された場合、いずれもより大きい 2 種類のオブジェクトのより大きい)。
解説
最大のアルゴリズムは、パラメーターとして渡されたオブジェクトを持つことにはほとんどありません。ほとんどの標準テンプレート ライブラリのアルゴリズムは位置がパラメーターとして反復子のパスで指定された要素の範囲を操作します。
使用例
// alg_max.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 absolute value of elem1 is greater than
// absolute value of elem2
bool abs_greater ( int elem1, int elem2 )
{
if ( elem1 < 0 )
elem1 = -elem1;
if ( elem2 < 0 )
elem2 = -elem2;
return elem1 < elem2;
};
int main( )
{
int a = 6, b = -7;
// Return the integer with the larger absolute value
const int& result1 = max(a, b, abs_greater);
// Return the larger integer
const int& result2 = max(a, b);
cout << "Using integers 6 and -7..." << endl;
cout << "The integer with the greater absolute value is: "
<< result1 << "." << endl;
cout << "The integer with the greater value is: "
<< result2 << "." << endl;
cout << endl;
// Comparing set containers with elements of type CInt
// using the max 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 = max ( s1, s2 );
cout << "s3 = max ( 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 the max 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 = max ( v1, v2 );
v5 = max ( v1, v3 );
cout << "Vector v4 = max (v1,v2) is ( " ;
for ( Iter4 = v4.begin( ) ; Iter4 != v4.end( ) ; Iter4++ )
cout << *Iter4 << " ";
cout << ")." << endl;
cout << "Vector v5 = max (v1,v3) is ( " ;
for ( Iter5 = v5.begin( ) ; Iter5 != v5.end( ) ; Iter5++ )
cout << *Iter5 << " ";
cout << ")." << endl;
}
必要条件
ヘッダー: algorithm
名前空間: std