#ifndef _random_h_INCLUDED
#define _random_h_INCLUDED
#include <assert.h>
#include <stdbool.h>
#include <stdint.h>
typedef uint64_t generator;
static inline uint64_t kissat_next_random64 (generator *rng) {
*rng *= 6364136223846793005ul;
*rng += 1442695040888963407ul;
return *rng;
}
static inline unsigned kissat_next_random32 (generator *rng) {
return kissat_next_random64 (rng) >> 32;
}
static inline unsigned kissat_pick_random (generator *rng, unsigned l,
unsigned r) {
assert (l <= r);
if (l == r)
return l;
const unsigned delta = r - l;
const unsigned tmp = kissat_next_random32 (rng);
const double fraction = tmp / 4294967296.0;
assert (0 <= fraction), assert (fraction < 1);
const unsigned scaled = delta * fraction;
assert (scaled < delta);
const unsigned res = l + scaled;
assert (l <= res), assert (res < r);
return res;
}
static inline bool kissat_pick_bool (generator *rng) {
return kissat_pick_random (rng, 0, 2);
}
static inline double kissat_pick_double (generator *rng) {
return kissat_next_random32 (rng) / 4294967296.0;
}
#endif