logical_or Struct
The struct provides a predefined function object that performs the logical operation of disjunction on elements of a specified value type and tests for the truth or falsity of the result.
template<class Type>
struct logical_or : public binary_function<Type, Type, bool>
{
bool operator()(
const Type& _Left,
const Type& _Right
) const;
};
Parameters
_Left
The left operand of type Type in the disjunction to be tested._Right
The right operand of type Type in the disjunction to be tested.
Return Value
true if _Left is true or _Right is true; false if and only if _Left is false and _Right is false.
Example
// functional_logical_or.cpp
// compile with: /EHsc
#include <deque>
#include <algorithm>
#include <functional>
#include <iostream>
int main( )
{
using namespace std;
deque <bool> d1, d2, d3( 7 );
deque <bool>::iterator iter1, iter2, iter3;
int i;
for ( i = 0 ; i < 7 ; i++ )
{
d1.push_back((bool)((rand() % 2) != 0));
}
int j;
for ( j = 0 ; j < 7 ; j++ )
{
d2.push_back((bool)((rand() % 2) != 0));
}
cout << boolalpha; // boolalpha I/O flag on
cout << "Original deque:\n d1 = ( " ;
for ( iter1 = d1.begin( ) ; iter1 != d1.end( ) ; iter1++ )
cout << *iter1 << " ";
cout << ")" << endl;
cout << "Original deque:\n d2 = ( " ;
for ( iter2 = d2.begin( ) ; iter2 != d2.end( ) ; iter2++ )
cout << *iter2 << " ";
cout << ")" << endl;
// To find element-wise disjunction of the truth values
// of d1 & d2, use the logical_or function object
transform( d1.begin( ), d1.end( ), d2.begin( ),
d3.begin( ), logical_or<bool>( ) );
cout << "The deque which is the disjuction of d1 & d2 is:\n d3 = ( " ;
for ( iter3 = d3.begin( ) ; iter3 != d3.end( ) ; iter3++ )
cout << *iter3 << " ";
cout << ")" << endl;
}
Original deque:
d1 = ( true true false false true false false )
Original deque:
d2 = ( false false false true true true true )
The deque which is the disjuction of d1 & d2 is:
d3 = ( true true false true true true true )
Requirements
Header: <functional>
Namespace: std