Add missing header

Author: WrathfulSpatula

FindAFactor/_find_a_factor.cpp

@@ -41,6 +41,7 @@
 #include "dispatchqueue.hpp"
 
 #include <algorithm>
+#include <cmath>
 #include <future>
 #include <iostream>
 #include <map>

setup.py

@@ -10,7 +10,7 @@
 if os.name == 'nt':
     cpp_args = ['/std:c++17', '/O3']
 else:
-    cpp_args = ['-std=c++17', '-O3', '-lpthread']
+    cpp_args = ['-O3', '-std=c++17', '-lpthread']
 
 README_PATH = os.path.join(os.path.abspath(os.path.dirname(__file__)), 'README.md')
 with open(README_PATH) as readme_file: