You have a bag of weights and a balance.
On one side of the balance is a target weight.
Write a method named canBalance
that accepts two parameters:
an integer representing the target weight that you want to balance,
and a list of positive integers, which represent your weights.
Your method should return true
if you can balance the scales, and false
otherwise.
For example, if you are trying to balance a target weight of [5]
using a bag of [1, 2, 6]
, this returns true
because you can put the [1]
with the [5]
, the [6]
on the other side, and leave the [2]
unused.
Or, as shown in the figures below, if you had a bag of [1, 3]
you could measure a weight of 4 or 2 by the following two arrangements:
You are allowed to modify the list passed in as the parameter as you compute the answer, as long as you restore it to its original form by the time the overall call is finished.
Do not use any loops in solving this problem.
Your code should use recursive backtracking.