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Hi everyone,

As part of an assignment we have to develop a recursive backtracking solution in java to a sort of knapsack problem - you have a 150mm bar, a set of orders you have to cut and you need to come up with the best solution that gets the most orders done with the least amount of waste.

So far I have this as my recursive method

```
// Returns the best possible solution where the most orders can be processed with
// the least amount of wastage
private SetInt tryCutting(SetInt possibleOrders, SetInt solution, int lengthLeft)
{
int i = 7;
// while possibleOrders Set is not empty
while (!possibleOrders.isEmpty())
{ int order = possibleOrders.min();
System.out.println("Order Selected : " + order);
System.out.println("Length Left : " + lengthLeft);
if (order <= lengthLeft)
{
solution.add(order);
System.out.println(order + " Added To Solution");
System.out.println(solution.numberInSet() + " Orders In Solution");
possibleOrders.remove(order);
lengthLeft -= order;
System.out.println("New Length Left : " + lengthLeft);
if(solution.numberInSet() != 7)
{
tryCutting(possibleOrders,solution,lengthLeft);
}
else
break;
}
else
break;
}
return solution;
}
```

But so far all it's good for is crashing your computer everytime you run it thanks to an infinite loop - it seems to take the first order from the set (3, 29, 25, 35, 20, 60, 40), then get stuck looping around and around trying to add 0 to the solution (we have to use a class SetInt where the value 0 is an illegal value)

Any help would be much appreciated, even just a hint in the right direction :)!