Thank you for your reply.
But it is hard to say which fruit is "required". As, for example, an
apple makes Allen happy, but if there is no apple, a banana may also
does. Each person may have may combinations of fruits which make them
happy. There are many choices with different cost for a people,
my idea,
say, fruit1 is required to make person A and person B happy.
person A requires num1 number of fruit1 and person B requires num2 number of fruit1.
then required number of fruit1 is max( num1 , num2 )
similary if you can extend this to all who require it and calculate the max require
