Thieves are here too!

My bike doesn't have a lock. I dont have enough money to buy it! Rinal and I share the lock. We tie our bikes together to common post. Yesterday we found that one of the bike was misssing. We first thought that one of our friend might have taken it. But at the close examination of lock , we found that someone had cut the lock. This really hurt us. Currently we are not earning even an extra dollar! The cutter he might have used would be amazing. Why do they sell lock which can be cut? I kept my bike in my drawing room to prevent it from being stolen. Never trust on lock!