What is the Fractional Knapsack problem and how can it be solved using a greedy algorithm?

Greedy Algorithms Questions



47 Short 31 Medium 80 Long Answer Questions Question Index

What is the Fractional Knapsack problem and how can it be solved using a greedy algorithm?

The Fractional Knapsack problem is a variation of the Knapsack problem where items can be divided into fractions. In this problem, we are given a set of items, each with a weight and a value, and a knapsack with a maximum weight capacity. The goal is to maximize the total value of the items placed in the knapsack without exceeding its weight capacity.

A greedy algorithm can be used to solve the Fractional Knapsack problem. The algorithm works by selecting items based on their value-to-weight ratio in a greedy manner.

Here are the steps to solve the problem using a greedy algorithm:

1. Calculate the value-to-weight ratio for each item by dividing its value by its weight.
2. Sort the items in descending order based on their value-to-weight ratio.
3. Initialize the total value and total weight of the knapsack to 0.
4. Iterate through the sorted items and add items to the knapsack as long as their weight does not exceed the knapsack's capacity.
5. If an item's weight exceeds the remaining capacity of the knapsack, take a fraction of it that can fit and calculate the corresponding value.
6. Update the total value and total weight of the knapsack accordingly.
7. Repeat steps 4-6 until all items have been considered or the knapsack is full.
8. Return the total value of the items in the knapsack.

By selecting items with the highest value-to-weight ratio first, the greedy algorithm ensures that the knapsack is filled with the most valuable items possible.