There is a trip between A to B of 100km.
It is divided into 5 parts of 20 km each
A man needs to cover this distance
He can cover 20 km in each day
At A unlimited quantity of food is there
For every 20 km the man needs to take 1 food
the man can carry a maximum of three foods
he can drop the food in between the path wherever he likes
how will he reach the destination