alenaPy · EgorPichkur · Jan 16, 2019 · Feb 28, 2019 · Feb 28, 2019 · Feb 28, 2019
diff --git a/homework3/sync_condition.py b/homework3/sync_condition.py
@@ -0,0 +1,34 @@
+"""Homework 3: Thread Synchronization Using Conditions"""
+
+from threading import Condition
+from threading import Thread
+
+
+def print_odd(cv):
+    """Function to print odd numbers"""
+    nums = [x for x in range(101) if x % 2 == 1]
+    for num in nums:
+        with cv:
+            cv.wait()
+            print(num)
+            cv.notify()
+
+
+def print_even(cv):
+    """Function to print even numbers"""
+    nums = [x for x in range(101) if x % 2 == 0]
+    for num in nums:
+        with cv:
+            print(num)
+            cv.notify()
+            if (num != 100):
+                cv.wait()
+
+
+if __name__ == '__main__':
+    condition = Condition()
+    odd = Thread(name='odd', target=print_odd, args=(condition,))
+    even = Thread(name='even', target=print_even, args=(condition,))
+
+    odd.start()
+    even.start()
diff --git a/homework3/sync_event.py b/homework3/sync_event.py
@@ -0,0 +1,42 @@
+"""Homework 3: Thread Synchronization Using Events"""
+
+from threading import Event
+from threading import Thread
+
+
+class EventThread(Thread):
+    """My thread to work with events"""
+
+    main_event = Event()
+
+    def __init__(self, thread_name):
+        super().__init__()
+
+        self.thread_name = thread_name
+
+        if self.thread_name == 'even':
+            self.nums = [x for x in range(101) if x % 2 == 0]
+        else:
+            self.nums = [x for x in range(101) if x % 2 == 1]
+
+    def run(self):
+        """Implementation of thread's activity"""
+
+        for num in self.nums:
+            if self.thread_name == 'even':
+                while self.main_event.isSet():
+                    pass
+                print(num)
+                self.main_event.set()
+            else:
+                self.main_event.wait()
+                print(num)
+                self.main_event.clear()
+
+
+if __name__ == '__main__':
+    even_thread = EventThread('even')
+    odd_thread = EventThread('odd')
+
+    odd_thread.start()
+    even_thread.start()
diff --git a/homework3/sync_lock.py b/homework3/sync_lock.py
@@ -0,0 +1,43 @@
+"""Homework 3: Thread Synchronization Using Locks"""
+
+from threading import Lock
+from threading import Thread
+
+
+class LockThread(Thread):
+    """My thread to work with locks"""
+
+    even_lock = Lock()
+    odd_lock = Lock()
+
+    def __init__(self, thread_name):
+        super().__init__()
+
+        self.thread_name = thread_name
+
+        if self.thread_name == 'even':
+            self.nums = [x for x in range(101) if x % 2 == 0]
+            self.odd_lock.acquire()
+        else:
+            self.nums = [x for x in range(101) if x % 2 == 1]
+
+    def run(self):
+        """Implementation of thread's activity"""
+
+        for num in self.nums:
+            if self.thread_name == 'even':
+                self.even_lock.acquire()
+                print(num)
+                self.odd_lock.release()
+            else:
+                self.odd_lock.acquire()
+                print(num)
+                self.even_lock.release()
+
+
+if __name__ == '__main__':
+    even_thread = LockThread('even')
+    odd_thread = LockThread('odd')
+
+    odd_thread.start()
+    even_thread.start()
diff --git a/homework3/sync_semaphore.py b/homework3/sync_semaphore.py
@@ -0,0 +1,41 @@
+"""Homework 3: Thread Synchronization Using Semaphores"""
+
+from threading import Semaphore
+from threading import Thread
+
+
+class SemaphoreThread(Thread):
+    """My thread to work with semaphores"""
+
+    even_sem = Semaphore(1)
+    odd_sem = Semaphore(0)
+
+    def __init__(self, thread_name):
+        super().__init__()
+
+        self.thread_name = thread_name
+        if self.thread_name == 'even':
+            self.nums = [x for x in range(101) if x % 2 == 0]
+        else:
+            self.nums = [x for x in range(101) if x % 2 == 1]
+
+    def run(self):
+        """Implementation of thread's activity"""
+
+        for num in self.nums:
+            if self.thread_name == 'even':
+                self.even_sem.acquire()
+                print(num)
+                self.odd_sem.release()
+            else:
+                self.odd_sem.acquire()
+                print(num)
+                self.even_sem.release()
+
+
+if __name__ == '__main__':
+    even_thread = SemaphoreThread('even')
+    odd_thread = SemaphoreThread('odd')
+
+    even_thread.start()
+    odd_thread.start()
diff --git a/homework3/sync_timer.py b/homework3/sync_timer.py
@@ -0,0 +1,24 @@
+"""Homework 3: Thread Synchronization Using Timer"""
+
+from threading import Timer
+from time import sleep
+
+
+def timer_thread(start_num, sleep_time):
+    for num in range(start_num, 101, 2):
+        print(num)
+        sleep(sleep_time)
+
+
+if __name__ == '__main__':
+    sleep_time = 1
+    even_start_num = 0
+    odd_start_num = 1
+
+    even_thread = Timer(sleep_time / 2, timer_thread,
+                        args=[even_start_num, sleep_time])
+    odd_thread = Timer(sleep_time, timer_thread,
+                       args=[odd_start_num, sleep_time])
+
+    even_thread.start()
+    odd_thread.start()