dist-javascript-algorithms-and-data-structures/dist/algorithms/sets/knapsack-problem/__test__/Knapsack.test.js

Algorithms and data-structures implemented on JavaScript

"use strict";

var _Knapsack = _interopRequireDefault(require("../Knapsack"));

var _KnapsackItem = _interopRequireDefault(require("../KnapsackItem"));

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

describe('Knapsack', () => {
  it('should solve 0/1 knapsack problem', () => {
    const possibleKnapsackItems = [new _KnapsackItem.default({
      value: 1,
      weight: 1
    }), new _KnapsackItem.default({
      value: 4,
      weight: 3
    }), new _KnapsackItem.default({
      value: 5,
      weight: 4
    }), new _KnapsackItem.default({
      value: 7,
      weight: 5
    })];
    const maxKnapsackWeight = 7;
    const knapsack = new _Knapsack.default(possibleKnapsackItems, maxKnapsackWeight);
    knapsack.solveZeroOneKnapsackProblem();
    expect(knapsack.totalValue).toBe(9);
    expect(knapsack.totalWeight).toBe(7);
    expect(knapsack.selectedItems.length).toBe(2);
    expect(knapsack.selectedItems[0].toString()).toBe('v5 w4 x 1');
    expect(knapsack.selectedItems[1].toString()).toBe('v4 w3 x 1');
  });
  it('should solve 0/1 knapsack problem regardless of items order', () => {
    const possibleKnapsackItems = [new _KnapsackItem.default({
      value: 5,
      weight: 4
    }), new _KnapsackItem.default({
      value: 1,
      weight: 1
    }), new _KnapsackItem.default({
      value: 7,
      weight: 5
    }), new _KnapsackItem.default({
      value: 4,
      weight: 3
    })];
    const maxKnapsackWeight = 7;
    const knapsack = new _Knapsack.default(possibleKnapsackItems, maxKnapsackWeight);
    knapsack.solveZeroOneKnapsackProblem();
    expect(knapsack.totalValue).toBe(9);
    expect(knapsack.totalWeight).toBe(7);
    expect(knapsack.selectedItems.length).toBe(2);
    expect(knapsack.selectedItems[0].toString()).toBe('v5 w4 x 1');
    expect(knapsack.selectedItems[1].toString()).toBe('v4 w3 x 1');
  });
  it('should solve 0/1 knapsack problem with impossible items set', () => {
    const possibleKnapsackItems = [new _KnapsackItem.default({
      value: 5,
      weight: 40
    }), new _KnapsackItem.default({
      value: 1,
      weight: 10
    }), new _KnapsackItem.default({
      value: 7,
      weight: 50
    }), new _KnapsackItem.default({
      value: 4,
      weight: 30
    })];
    const maxKnapsackWeight = 7;
    const knapsack = new _Knapsack.default(possibleKnapsackItems, maxKnapsackWeight);
    knapsack.solveZeroOneKnapsackProblem();
    expect(knapsack.totalValue).toBe(0);
    expect(knapsack.totalWeight).toBe(0);
    expect(knapsack.selectedItems.length).toBe(0);
  });
  it('should solve 0/1 knapsack problem with all equal weights', () => {
    const possibleKnapsackItems = [new _KnapsackItem.default({
      value: 5,
      weight: 1
    }), new _KnapsackItem.default({
      value: 1,
      weight: 1
    }), new _KnapsackItem.default({
      value: 7,
      weight: 1
    }), new _KnapsackItem.default({
      value: 4,
      weight: 1
    }), new _KnapsackItem.default({
      value: 4,
      weight: 1
    }), new _KnapsackItem.default({
      value: 4,
      weight: 1
    })];
    const maxKnapsackWeight = 3;
    const knapsack = new _Knapsack.default(possibleKnapsackItems, maxKnapsackWeight);
    knapsack.solveZeroOneKnapsackProblem();
    expect(knapsack.totalValue).toBe(16);
    expect(knapsack.totalWeight).toBe(3);
    expect(knapsack.selectedItems.length).toBe(3);
    expect(knapsack.selectedItems[0].toString()).toBe('v4 w1 x 1');
    expect(knapsack.selectedItems[1].toString()).toBe('v5 w1 x 1');
    expect(knapsack.selectedItems[2].toString()).toBe('v7 w1 x 1');
  });
  it('should solve unbound knapsack problem', () => {
    const possibleKnapsackItems = [new _KnapsackItem.default({
      value: 84,
      weight: 7
    }), // v/w ratio is 12
    new _KnapsackItem.default({
      value: 5,
      weight: 2
    }), // v/w ratio is 2.5
    new _KnapsackItem.default({
      value: 12,
      weight: 3
    }), // v/w ratio is 4
    new _KnapsackItem.default({
      value: 10,
      weight: 1
    }), // v/w ratio is 10
    new _KnapsackItem.default({
      value: 20,
      weight: 2
    })];
    const maxKnapsackWeight = 15;
    const knapsack = new _Knapsack.default(possibleKnapsackItems, maxKnapsackWeight);
    knapsack.solveUnboundedKnapsackProblem();
    expect(knapsack.totalValue).toBe(84 + 20 + 12 + 10 + 5);
    expect(knapsack.totalWeight).toBe(15);
    expect(knapsack.selectedItems.length).toBe(5);
    expect(knapsack.selectedItems[0].toString()).toBe('v84 w7 x 1');
    expect(knapsack.selectedItems[1].toString()).toBe('v20 w2 x 1');
    expect(knapsack.selectedItems[2].toString()).toBe('v10 w1 x 1');
    expect(knapsack.selectedItems[3].toString()).toBe('v12 w3 x 1');
    expect(knapsack.selectedItems[4].toString()).toBe('v5 w2 x 1');
  });
  it('should solve unbound knapsack problem with items in stock', () => {
    const possibleKnapsackItems = [new _KnapsackItem.default({
      value: 84,
      weight: 7,
      itemsInStock: 3
    }), // v/w ratio is 12
    new _KnapsackItem.default({
      value: 5,
      weight: 2,
      itemsInStock: 2
    }), // v/w ratio is 2.5
    new _KnapsackItem.default({
      value: 12,
      weight: 3,
      itemsInStock: 1
    }), // v/w ratio is 4
    new _KnapsackItem.default({
      value: 10,
      weight: 1,
      itemsInStock: 6
    }), // v/w ratio is 10
    new _KnapsackItem.default({
      value: 20,
      weight: 2,
      itemsInStock: 8
    })];
    const maxKnapsackWeight = 17;
    const knapsack = new _Knapsack.default(possibleKnapsackItems, maxKnapsackWeight);
    knapsack.solveUnboundedKnapsackProblem();
    expect(knapsack.totalValue).toBe(84 + 84 + 20 + 10);
    expect(knapsack.totalWeight).toBe(17);
    expect(knapsack.selectedItems.length).toBe(3);
    expect(knapsack.selectedItems[0].toString()).toBe('v84 w7 x 2');
    expect(knapsack.selectedItems[1].toString()).toBe('v20 w2 x 1');
    expect(knapsack.selectedItems[2].toString()).toBe('v10 w1 x 1');
  });
  it('should solve unbound knapsack problem with items in stock and max weight more than sum of all items', () => {
    const possibleKnapsackItems = [new _KnapsackItem.default({
      value: 84,
      weight: 7,
      itemsInStock: 3
    }), // v/w ratio is 12
    new _KnapsackItem.default({
      value: 5,
      weight: 2,
      itemsInStock: 2
    }), // v/w ratio is 2.5
    new _KnapsackItem.default({
      value: 12,
      weight: 3,
      itemsInStock: 1
    }), // v/w ratio is 4
    new _KnapsackItem.default({
      value: 10,
      weight: 1,
      itemsInStock: 6
    }), // v/w ratio is 10
    new _KnapsackItem.default({
      value: 20,
      weight: 2,
      itemsInStock: 8
    })];
    const maxKnapsackWeight = 60;
    const knapsack = new _Knapsack.default(possibleKnapsackItems, maxKnapsackWeight);
    knapsack.solveUnboundedKnapsackProblem();
    expect(knapsack.totalValue).toBe(3 * 84 + 2 * 5 + 1 * 12 + 6 * 10 + 8 * 20);
    expect(knapsack.totalWeight).toBe(3 * 7 + 2 * 2 + 1 * 3 + 6 * 1 + 8 * 2);
    expect(knapsack.selectedItems.length).toBe(5);
    expect(knapsack.selectedItems[0].toString()).toBe('v84 w7 x 3');
    expect(knapsack.selectedItems[1].toString()).toBe('v20 w2 x 8');
    expect(knapsack.selectedItems[2].toString()).toBe('v10 w1 x 6');
    expect(knapsack.selectedItems[3].toString()).toBe('v12 w3 x 1');
    expect(knapsack.selectedItems[4].toString()).toBe('v5 w2 x 2');
  });
});