쓰레드 동기화 문제

thread-global-variable.py

import threading

# 전역 변수
r = 0

class Consumer(threading.Thread):        
    def run(self):        
        global r
        for _ in range(1000000):
            r += 1
            
class Producer(threading.Thread):
    def run(self):
        global r
        for _ in range(1000000):
            r -= 1
            
Producer().start()
Consumer().start()
print(r)