.TH ZBITS 3 libzahl
.SH NAME
zbits - Count used bits in a big integer
.SH SYNOPSIS
.nf
#include <zahl.h>

size_t zbits(z_t \fIa\fP);
.fi
.SH DESCRIPTION
.B zbits
calculates the bit-size of
.IR a .
If
.I a
is zero the bit-size is 1.
.SH RETURN VALUE
.B zbits
returns the number of bits requires
to represent
.I a
\(em 1 plus the floored binary logarithm of the
absolute value of
.I a
\(em or 1 if
.I a
is zero.
.SH SEE ALSO
.BR zlsb (3),
.BR zzero (3)