bitset::test
Tests whether the bit at a specified position in a bitset is set to 1.
bool test(
size_t _Pos,
) const;
Parameters
- _Pos
The position of the bit in the bitset to be tested for its value.
Return Value
true if the bit specified by the argument position is set to 1; otherwise, false.
Remarks
The member function throws an out_of_range exception that is the size of the bitset is less than or equal to the position specified in the argument.
Example
// bitset_test.cpp
// compile with: /EHsc
#include <bitset>
#include <iostream>
int main( )
{
using namespace std;
bitset<5> b1 ( 6 );
bool b;
bitset<5>::element_type e;
cout << "Original bitset b1(6) is: ( "<< b1 << " )"
<< endl;
cout << "Note: positions in a bitset are numbered\n"
<< " from the right starting with 0.\n" << endl;
b = b1.test ( 3 );
if ( b )
cout << "The bit at position 3 of bitset b1 "
<< "has a value of 1." << endl;
else
cout << "The bit at position 3 of bitset b1 "
<< "has a value of 0." << endl;
b1[3] = 1;
cout << "Bitset b1 modified by b1[3] = 1 is: ( "<< b1 << " )"
<< endl;
e = b1.test ( 3 );
if ( e )
cout << "The bit at position 3 of bitset b1 "
<< "has a value of 1." << endl;
else
cout << "The bit at position 3 of bitset b1 "
<< "has a value of 0." << endl;
}
Original bitset b1(6) is: ( 00110 )
Note: positions in a bitset are numbered
from the right starting with 0.
The bit at position 3 of bitset b1 has a value of 0.
Bitset b1 modified by b1[3] = 1 is: ( 01110 )
The bit at position 3 of bitset b1 has a value of 1.
Requirements
Header: <bitset>
Namespace: std