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#include "pcg.h"
// Random number generator.// Based on:// *Really* minimal PCG32 code / (c) 2014 M.E. O'Neill / pcg-random.org// Licensed under Apache License 2.0 (NO WARRANTY, etc. see website)
uint64_t state = 0x853c49e6748fea9bULL;uint64_t inc   = 0xda3e39cb94b95bdbULL;
// Update seed of generator.void pcg_seed(uint64_t seed) {  state = seed;}
// Generate random integer.uint32_t pcg_rand() {    uint64_t oldstate = state;    // Advance internal state    state = oldstate * 6364136223846793005ULL + (inc|1);    // Calculate output function (XSH RR), uses old state for max ILP    uint32_t xorshifted = ((oldstate >> 18u) ^ oldstate) >> 27u;    uint32_t rot = oldstate >> 59u;    return (xorshifted >> rot) | (xorshifted << ((-rot) & 31));}
// Fill out buffer with size random bytes.void pcg_bytes(char* out, int size) {  // TODO: We can be more efficient by using all 4  //       pieces of the random number returned.  for (int i = 0; i < size; i ++) {    out[i] = (char)pcg_rand();  }}