Sonu has to deliver seven parcels containing different items- Medicine, Book, Stationery, Grocery, Cosmetics, Clothe and Chocolate to houses on different floors of a building, one parcel each to a house. The seven floors of the building are numbered consecutively 1 through 7. Delivery of parcels to houses must meet the following conditions:
i. Medicine is delivered on a lower numbered floor than Grocery.
ii. Clothe is delivered at one level below the floor at which Book is delivered.
iii. Stationery is delivered at first floor or else seventh floor.
iv. Chocolate is delivered at fourth floor.