From 1c4b0813fced1e6e49999e2ef49177b23d0661c5 Mon Sep 17 00:00:00 2001
From: Trivernis <trivernis@gmail.com>
Date: Mon, 27 Jan 2020 09:27:01 +0100
Subject: [PATCH] Add program and README

---
 .gitignore           |  3 +++
 .idea/.gitignore     |  2 ++
 .idea/.name          |  1 +
 .idea/c++-primes.iml |  2 ++
 .idea/discord.xml    |  9 +++++++++
 .idea/misc.xml       |  7 +++++++
 .idea/modules.xml    |  8 ++++++++
 .idea/vcs.xml        |  6 ++++++
 CMakeLists.txt       |  6 ++++++
 README.md            | 12 ++++++++++-
 main.cpp             | 47 ++++++++++++++++++++++++++++++++++++++++++++
 11 files changed, 102 insertions(+), 1 deletion(-)
 create mode 100644 .gitignore
 create mode 100644 .idea/.gitignore
 create mode 100644 .idea/.name
 create mode 100644 .idea/c++-primes.iml
 create mode 100644 .idea/discord.xml
 create mode 100644 .idea/misc.xml
 create mode 100644 .idea/modules.xml
 create mode 100644 .idea/vcs.xml
 create mode 100644 CMakeLists.txt
 create mode 100644 main.cpp

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ab155e2
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,3 @@
+cmake-build-debug
+primes.txt
+main
\ No newline at end of file
diff --git a/.idea/.gitignore b/.idea/.gitignore
new file mode 100644
index 0000000..5c98b42
--- /dev/null
+++ b/.idea/.gitignore
@@ -0,0 +1,2 @@
+# Default ignored files
+/workspace.xml
\ No newline at end of file
diff --git a/.idea/.name b/.idea/.name
new file mode 100644
index 0000000..c773b40
--- /dev/null
+++ b/.idea/.name
@@ -0,0 +1 @@
+c___primes
\ No newline at end of file
diff --git a/.idea/c++-primes.iml b/.idea/c++-primes.iml
new file mode 100644
index 0000000..f08604b
--- /dev/null
+++ b/.idea/c++-primes.iml
@@ -0,0 +1,2 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<module classpath="CMake" type="CPP_MODULE" version="4" />
\ No newline at end of file
diff --git a/.idea/discord.xml b/.idea/discord.xml
new file mode 100644
index 0000000..59b11d1
--- /dev/null
+++ b/.idea/discord.xml
@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="DiscordProjectSettings">
+    <option name="show" value="true" />
+  </component>
+  <component name="ProjectNotificationSettings">
+    <option name="askShowProject" value="false" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
new file mode 100644
index 0000000..8822db8
--- /dev/null
+++ b/.idea/misc.xml
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CMakeWorkspace" PROJECT_DIR="$PROJECT_DIR$" />
+  <component name="JavaScriptSettings">
+    <option name="languageLevel" value="ES6" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
new file mode 100644
index 0000000..58390c1
--- /dev/null
+++ b/.idea/modules.xml
@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/c++-primes.iml" filepath="$PROJECT_DIR$/.idea/c++-primes.iml" />
+    </modules>
+  </component>
+</project>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
new file mode 100644
index 0000000..94a25f7
--- /dev/null
+++ b/.idea/vcs.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>
\ No newline at end of file
diff --git a/CMakeLists.txt b/CMakeLists.txt
new file mode 100644
index 0000000..f676b79
--- /dev/null
+++ b/CMakeLists.txt
@@ -0,0 +1,6 @@
+cmake_minimum_required(VERSION 3.15)
+project(c___primes)
+
+set(CMAKE_CXX_STANDARD 20)
+
+add_executable(c___primes main.cpp)
\ No newline at end of file
diff --git a/README.md b/README.md
index b3373c5..ece62e2 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,11 @@
-c++-primes
+# Primes in c++
+
+## Usage
+
+```bash
+# build
+g++ -lpthread -o main main.cpp
+
+# run
+./main
+```
diff --git a/main.cpp b/main.cpp
new file mode 100644
index 0000000..02a5bcc
--- /dev/null
+++ b/main.cpp
@@ -0,0 +1,47 @@
+#include <iostream>
+#include <pthread.h>
+#include <tuple>
+#include <thread>
+
+using namespace std;
+using std::cout;
+
+uint numThreads;
+
+void *GetPrimes(void* start) {
+    ulong num = (ulong) start;
+    ulong incr = numThreads * 2;
+    while (true) {
+        bool  isPrime = true;
+        if (num < 3 || num % 2 == 0) {
+            num += incr;
+            continue;
+        }
+        for (int i = 3; i < num/2; i += 2) {
+            if (num % i == 0) {
+                isPrime = false;
+                break;
+            }
+        }
+        if (isPrime) {
+            cout << num << "\n";
+        }
+        num += incr;
+    }
+}
+
+int main() {
+    numThreads = thread::hardware_concurrency();
+    pthread_t threads[numThreads];
+    long start = 1;
+    int rc;
+    for (int i = 0; i < numThreads; i++) {
+        rc = pthread_create(&threads[i], NULL, GetPrimes, (void *)(start + (2*i)));
+        if (rc) {
+            cout << "Error";
+            exit(-1);
+        }
+    }
+    pthread_exit(NULL);
+}
+