diff options
Diffstat (limited to 'util/random.h')
-rw-r--r-- | util/random.h | 11 |
1 files changed, 5 insertions, 6 deletions
diff --git a/util/random.h b/util/random.h index ddd51b1..fe76ab4 100644 --- a/util/random.h +++ b/util/random.h @@ -5,7 +5,7 @@ #ifndef STORAGE_LEVELDB_UTIL_RANDOM_H_ #define STORAGE_LEVELDB_UTIL_RANDOM_H_ -#include <stdint.h> +#include <cstdint> namespace leveldb { @@ -15,6 +15,7 @@ namespace leveldb { class Random { private: uint32_t seed_; + public: explicit Random(uint32_t s) : seed_(s & 0x7fffffffu) { // Avoid bad seeds. @@ -23,8 +24,8 @@ class Random { } } uint32_t Next() { - static const uint32_t M = 2147483647L; // 2^31-1 - static const uint64_t A = 16807; // bits 14, 8, 7, 5, 2, 1, 0 + static const uint32_t M = 2147483647L; // 2^31-1 + static const uint64_t A = 16807; // bits 14, 8, 7, 5, 2, 1, 0 // We are computing // seed_ = (seed_ * A) % M, where M = 2^31-1 // @@ -54,9 +55,7 @@ class Random { // Skewed: pick "base" uniformly from range [0,max_log] and then // return "base" random bits. The effect is to pick a number in the // range [0,2^max_log-1] with exponential bias towards smaller numbers. - uint32_t Skewed(int max_log) { - return Uniform(1 << Uniform(max_log + 1)); - } + uint32_t Skewed(int max_log) { return Uniform(1 << Uniform(max_log + 1)); } }; } // namespace leveldb |