# Which algorithm is best for knapsack problem?

## Which algorithm is best for knapsack problem?

A greedy algorithm is the most straightforward approach to solving the knapsack problem, in that it is a one-pass algorithm that constructs a single final solution. At each stage of the problem, the greedy algorithm picks the option that is locally optimal, meaning it looks like the most suitable option right now.

What is knapsack algorithm with example?

The 0/1 knapsack problem means that the items are either completely or no items are filled in a knapsack. For example, we have two items having weights 2kg and 3kg, respectively. If we pick the 2kg item then we cannot pick 1kg item from the 2kg item (item is not divisible); we have to pick the 2kg item completely.

Is knapsack a problem with NP?

Knapsack is NP-hard through a reduction from the partition problem (see 10.5). Using dynamic programming, we can get an exact solution for knapsack in time O(poly(n, Pmax)× log (nB)). Unfortunately, this is not polynomial in the size of its representation – Pmax is actu- ally log Pmax in the problem representation.

### Is knapsack NP-hard or NP-complete?

Theorem 1 Knapsack is NP-complete. Proof: First of all, Knapsack is NP. The proof is the set S of items that are chosen and the verification process is to compute ∑i∈S si and ∑i∈S vi, which takes polynomial time in the size of input.

What is knapsack problem greedy algorithm?

Knapsack Problem Given a set of items, each with a weight and a value, determine a subset of items to include in a collection so that the total weight is less than or equal to a given limit and the total value is as large as possible. The knapsack problem is in combinatorial optimization problem.

Which of the following algorithm design methods can produce algorithms for solving 0 1 knapsack problem with an optimal solution?

The 0-1 Knapsack problem can be solved using Greedy algorithm.

#### Is knapsack a Greedy algorithm?

The knapsack problem is one of the famous and important problems that come under the greedy method. As this problem is solved using a greedy method, this problem is one of the optimization problems, more precisely a combinatorial optimization.

What is the difference between a knapsack and a backpack?

Actually the main difference between a knapsack and backpack are that usually backpacks are large bags designed with shoulder straps and equipped with handles (usually two). A knapsack is small bag meant to carry items such as clothes, books, shoes or any other small items.

How does knapsack algorithm work?

The Knapsack Problem is a really interesting problem in combinatorics — to cite Wikipedia, “given a set of items, each with a weight and a value, determine the number of each item to include in a collection so that the total weight is less than or equal to a given limit and the total value is as large as possible.”

## Can knapsack be done in polynomial time?

The running time is O(NW) for an unbounded knapsack problem with N items and knapsack of size W. W is not polynomial in the length of the input though, which is what makes it pseudo-polynomial.

Can knapsack be solved by greedy algorithm?

The Greedy algorithm could be understood very well with a well-known problem referred to as Knapsack problem. Although the same problem could be solved by employing other algorithmic approaches, Greedy approach solves Fractional Knapsack problem reasonably in a good time.

Can knapsack problem be solved by dynamic programming?

In this Knapsack algorithm type, each package can be taken or not taken. Besides, the thief cannot take a fractional amount of a taken package or take a package more than once. This type can be solved by Dynamic Programming Approach.

### What is the time complexity of knapsack problem?

Time complexity for 0/1 Knapsack problem solved using DP is O(N*W) where N denotes number of items available and W denotes the capacity of the knapsack.

Which greedy strategy is useful to solve knapsack problem?

The basic idea of the greedy approach is to calculate the ratio value/weight for each item and sort the item on basis of this ratio. Then take the item with the highest ratio and add them until we can’t add the next item as a whole and at the end add the next item as much as we can.

Why is a knapsack called a knapsack?

It comes from the German knappen, “to bite,” and some experts believe that the name evolved from the fact that soldiers carried food in their knapsacks.

#### What is greedy algorithm for knapsack problem?

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