using System;

namespace Algorithms.Knapsack;

/// <summary>
///     Solves knapsack problem using some heuristics
///     Sum of values of taken items -> max
///     Sum of weights of taken items. &lt;= capacity.
/// </summary>
/// <typeparam name="T">Type of items in knapsack.</typeparam>
public interface IHeuristicKnapsackSolver<T>
{
    /// <summary>
    ///     Solves knapsack problem using some heuristics
    ///     Sum of values of taken items -> max
    ///     Sum of weights of taken items. &lt;= capacity.
    /// </summary>
    /// <param name="items">All items to choose from.</param>
    /// <param name="capacity">How much weight we can take.</param>
    /// <param name="weightSelector">Maps item to its weight.</param>
    /// <param name="valueSelector">Maps item to its value.</param>
    /// <returns>Items that were chosen.</returns>
    T[] Solve(T[] items, double capacity, Func<T, double> weightSelector, Func<T, double> valueSelector);
}