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//------------------------------------------------------------------------------
// GraphBLAS/Demo/Include/simple_rand.h: a very simple random number generator
//------------------------------------------------------------------------------
// SuiteSparse:GraphBLAS, Timothy A. Davis, (c) 2017-2025, All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0
//------------------------------------------------------------------------------
#ifndef SIMPLE_RAND_H
#define SIMPLE_RAND_H
#include <stdint.h>
// return a random number between 0 and UINT64_MAX
static inline uint64_t simple_rand (uint64_t *state)
{
uint64_t s = (*state) ;
s ^= s << 13 ;
s ^= s >> 7 ;
s ^= s << 17 ;
return ((*state) = s) ;
}
// return a random double between 0 and 1, inclusive
static inline double simple_rand_x (uint64_t *state)
{
return (((double) simple_rand (state)) / ((double) UINT64_MAX)) ;
}
#endif
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