A Lady (L) bought an item of Rs 100 from the Shopkeeper (C). She paid him with a 500 Rs Note. Realizing that he did not have a change, the shopkeeper C got change for that note from another shopkeeper (S) and paid Rs 400 to the Lady.
After a few days, S realized that the note is fake, And he railed at C and took 500 Rs back from him.
So in this whole process, how much money did C lose in the end?