From: Marco Costalba <mcostalba@gmail.com>
Date: Mon, 31 Dec 2012 10:57:49 +0000 (+0100)
Subject: Allow to pass a 'seed' to RKISS
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=896420b1661d3ec1247487dbaf73e05546a1d625

Allow to pass a 'seed' to RKISS

This somewhat simplifies the code.

Suggested by Lucas Braesch.

No functional change.
---

diff --git a/src/book.cpp b/src/book.cpp
index 1c2d30e0..d75d63f9 100644
--- a/src/book.cpp
+++ b/src/book.cpp
@@ -348,11 +348,7 @@ namespace {
 
 } // namespace
 
-PolyglotBook::PolyglotBook() {
-
-  for (int i = Time::now() % 10000; i > 0; i--)
-      RKiss.rand<unsigned>(); // Make random number generation less deterministic
-}
+PolyglotBook::PolyglotBook() : RKiss(Time::now() % 10000) {}
 
 PolyglotBook::~PolyglotBook() { if (is_open()) close(); }
 
diff --git a/src/rkiss.h b/src/rkiss.h
index 154f3ca2..54bcab44 100644
--- a/src/rkiss.h
+++ b/src/rkiss.h
@@ -61,17 +61,15 @@ class RKISS {
     return s.d = e + s.a;
   }
 
-  // Init seed and scramble a few rounds
-  void raninit() {
+public:
+  RKISS(int seed = 73) {
 
     s.a = 0xf1ea5eed;
     s.b = s.c = s.d = 0xd4e12c77;
-    for (int i = 0; i < 73; i++)
+    for (int i = 0; i < seed; i++) // Scramble a few rounds
         rand64();
   }
 
-public:
-  RKISS() { raninit(); }
   template<typename T> T rand() { return T(rand64()); }
 };