public member function
<bitset>

std::bitset::test

bool test ( size_t pos ) const;
Return bit value
Returns whether bit at position pos in the bitset is set.

Unlike access operator ([]), this function performs a range check on pos before retrieveing the bit value.

Parameters

pos
Order position of the bit whose value is retrieved.
Order positions are counted from the rightmost bit, which is order position 0.
size_t is an unsigned integral type.

Return value

true if bit at position pos is set, and false otherwise.

If pos is not a valid bit position, out_of_range is thrown.

Example

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// bitset::test
#include <iostream>
#include <string>
#include <bitset>
using namespace std;

int main ()
{
  bitset<5> mybits (string("01011"));

  cout << "mybits contains:\n";
  cout << boolalpha;
  for (size_t i=0; i<mybits.size(); ++i)
    cout << mybits.test(i) << endl;

  return 0;
}


Output:
mybits contains:
true
true
false
true
false

See also

bitset::operator[]
Access bit (public member function)
bitset::count
Count bits set (public member function)
bitset::any
Test if any bit is set (public member function)
bitset::none
Test if no bit is set (public member function)