From 725f9dec4e7927297938ee99faa5400d9af3be9f Mon Sep 17 00:00:00 2001
From: Tom Smeding <tom.smeding@gmail.com>
Date: Sat, 20 Apr 2019 10:38:59 +0200
Subject: Use C++ <random> in normal aberth

---
 aberth/aberth.cpp | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

(limited to 'aberth')

diff --git a/aberth/aberth.cpp b/aberth/aberth.cpp
index 295e99c..02768e2 100644
--- a/aberth/aberth.cpp
+++ b/aberth/aberth.cpp
@@ -5,12 +5,12 @@
 #include <array>
 #include <string>
 #include <complex>
+#include <random>
 #include <utility>
 #include <tuple>
 #include <algorithm>
 #include <thread>
 #include <mutex>
-#include <cstdlib>
 #include <cstdint>
 #include <cassert>
 #include "../lodepng.h"
@@ -109,6 +109,8 @@ static double maxRootNorm(const Poly &poly) {
 	return 1 + value;
 }
 
+static thread_local minstd_rand randgenerator = minstd_rand(random_device()());
+
 struct AberthState {
 	const Poly &poly;
 	Poly deriv;
@@ -117,7 +119,9 @@ struct AberthState {
 	double radius;
 
 	void regenerate() {
-		auto genCoord = [this]() { return (double)random() / INT_MAX * 2 * radius - radius; };
+		auto genCoord = [this]() {
+			return uniform_real_distribution<double>(-radius, radius)(randgenerator);
+		};
 		for (int i = 0; i < N; i++) {
 			approx[i] = Com(genCoord(), genCoord());
 		}
@@ -387,8 +391,6 @@ static vector<int32_t> invoke_kernel(
 }
 
 int main(int argc, char **argv) {
-	srandomdev();
-
 	int W, H;
 	vector<int> counts;
 
-- 
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