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/**
* @license Apache-2.0
*
* Copyright (c) 2026 The Stdlib Authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
*    http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
 
'use strict';
 
// MODULES //
 
var factory = require( './factory.js' );
var randuint32 = require( './rand_uint32.js' );
 
 
// MAIN //
 
/**
* Generates a pseudorandom unsigned 32-bit integer via the xorshift32 algorithm.
*
* ## Method
*
* XorShift generators are a class of pseudorandom number generators discovered
* by George Marsaglia. They operate by repeated application of the exclusive or
* (XOR) operation combined with bit shifts.
*
* The xorshift32 algorithm uses the state recurrence
*
* ```tex
* x \leftarrow x \oplus (x \ll a_1) \\
* x \leftarrow x \oplus (x \gg a_2) \\
* x \leftarrow x \oplus (x \ll a_3)
* ```
*
* where \\(\oplus\\) denotes the bitwise exclusive or operator and the shift
* triplet \\((a_1, a_2, a_3)\\) is chosen to ensure the generator has a full
* period of \\(2^{32} - 1\\).
*
* In this implementation, the shift triplet is
*
* ```tex
* (a_1, a_2, a_3) = (13, 17, 5)
* ```
*
* as proposed by Marsaglia (2003). The state must be a non-zero unsigned 32-bit
* integer; a zero seed is replaced with \\(1\\) to avoid the degenerate
* all-zeros state.
*
* ## Notes
*
* -   The generator has a period of \\(2^{32} - 1\\) (all non-zero 32-bit states
*     are visited exactly once before the sequence repeats).
*
* -   The output range is between 1 to 2^32 - 1 (zero is never produced).
*
* -   The `normalized` property returns values on \\((0, 1]\\) by dividing the
*     raw output by \\(2^{32} - 1\\).
*
* ## References
*
* -   Marsaglia, George. 2003. "Xorshift RNGs." _Journal of Statistical
*     Software_ 8 (14). doi:[10.18637/jss.v008.i14](https://doi.org/10.18637/jss.v008.i14).
*
* @function xorshift32
* @type {PRNG}
* @returns {NonNegativeInteger} pseudorandom unsigned 32-bit integer
*
* @example
* var v = xorshift32();
* // returns <number>
*/
var xorshift32 = factory({
	'seed': randuint32()
});
 
 
// EXPORTS //
 
module.exports = xorshift32;