/*
  Smallest Integer from Array
  Write a function: function smallestInt(A);
  that, given an array A of N integers, returns the smallest positive integer (greater than 0) that does not occur in A.
  Example: given A = [1, 3, 6, 4, 1, 2], the function should return 5.
  Given A = [1, 2, 3], the function should return 4.
  Given A = [-1, -3], the function should return 1.
  Write an efficient algorithm for the following assumptions:
  N is an integer within the range [1..100,000];
  each element of array A is an integer within the range [−1,000,000..1,000,000].
  Write test cases to validate that your implementation conforms to the specification.
  Additionally, implement the benchmark function to test the performance of your solution. The benchmark should be able to run in the browser and be capable of outputting a reasonably reliable score when comparing solutions in the same environment.
  You will be evaluated based on:
  - Correctness according to instructions
  - Algorithmic efficiency
  - Scope of test cases
  - Code style and quality
  You're advised to include any less efficient solutions or pseudo code definitions of such solutions in your final submission.
*/

function smallestInt(A) {
  // Create Object & Set Values with Array
  let obj = {};
  for(let num of A) {
    obj[num] = 1;
  }
  // Set Bounds  - [1..100000]
  let setBounds = (n) => {
    n = n >= 1 ? n : 1;
    n = n <= 100000 ? n : 100000;
    return n;
  };
  let min = setBounds(Math.min(...A));
  let max = setBounds(Math.max(...A));
  // Find Missing Int
  for (let i = min; i < A.length + max; i++) {
    if ( !(i in obj) ) { return i; }
  }
}

function runTests() {
  describe('smallestInt', function() {
    it('should return the first missing positive number', function() {
      expect(smallestInt([-1,1,3,4,2])).toBe(5)
    });
    it('should return a positive number within range of 1 to 100,000', function() {
      expect(smallestInt([99999,100002,100050])).toBe(100000)
    });
  })
}

function runBenchmark() {
  // Array Testing - Amount of Int Values in Test Array
  const arrMin = 10;
  const arrMax = 50;
  // Value Bounds
  const intMin = -1000000;
  const intMax = 1000000;
  // Iterations
  const iterations = 11;
  let opts = [];
  // Benchmark Loop Tests
  for (let i = 1; i < iterations; i++) {
    // Set Amount of Items
    let arrCount = Math.floor(Math.random() * (arrMax - arrMin + 1)) + arrMin;
    let arr = []
    // Add Items to Array
    for (let t = 1; t < arrCount; t++) {
      arr.push(Math.floor(Math.random() * (intMax - intMin + 1)) + intMin);
    }
    // Browser Testing
    let start = window.performance.now();
    let num = smallestInt(arr);
    let end = window.performance.now();
    let time = end-start;
    // Output
    opts.push({
      iteration: i,
      time: `${time.toFixed(4)}ms`,
      size: `${arrCount} Items`,
      number: num,
      array: arr
    });
  }
  console.table(opts);
}