php man page for gmp_popcount

GMP_POPCOUNT(3) 							 1							   GMP_POPCOUNT(3)

gmp_popcount - Population count

SYNOPSIS
       int gmp_popcount (GMP  $a)

DESCRIPTION
	Get the population count.

PARAMETERS
	      o $a
		-Either  a  GMP number resource in PHP 5.5 and earlier, a GMP object in PHP 5.6 and later, or a numeric string provided that it is
		possible to convert the latter to a number.

RETURN VALUES
	The population count of $a, as an integer.

EXAMPLES
       Example #1

	      gmp_popcount(3) example

	      <?php
	      $pop1 = gmp_init("10000101", 2); // 3 1's
	      echo gmp_popcount($pop1) . "
";
	      $pop2 = gmp_init("11111110", 2); // 7 1's
	      echo gmp_popcount($pop2) . "
";
	      ?>

	      The above example will output:

	      3
	      7

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