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<P>©Copyright 1996 Rogue Wave Software</P>
<H2>Boolean Vectors</H2>
<P>Vectors of bit values (boolean 1/0 values) are handled as a special case by the standard library, so that the values can be efficiently packed (several elements to a word). The operations for a boolean vector , <B><I>vector<bool></I></B>, are a superset of those for an ordinary vector, only the implementation is more efficient.</P>
<P>One new member function added to the boolean vector data type is <SAMP>flip().</SAMP> When invoked, this function inverts all the bits of the vector. Boolean vectors also return as reference an internal value that also supports the <SAMP>flip()</SAMP> member function.</P>
<PRE> vector<bool> bvec(27);
bvec.flip(); // flip all values
bvec[17].flip(); // flip bit 17</PRE>
<P><B><I>vector<bool></I></B> also supports an additional <SAMP>swap()</SAMP> member function that allows you to swap the values indicated by a pair of references. </P>
<PRE> bvec.swap(bvec [17], bvec [16]);</PRE>
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