Aleph Tech Interview Problem

index.js

/** 

Given an integer array arr of distinct integers and an integer k.
A game will be played between the first two elements of the array (i.e. arr[0] and arr[1]). In each round of the game, we compare arr[0] with arr[1], the larger integer wins and remains at position 0, and the smaller integer moves to the end of the array. The game ends when an integer wins k consecutive rounds.
Return the integer which will win the game.
It is guaranteed that there will be a winner of the game.

Example 1:
Input: arr = [2,1,3,5,4,6,7], k = 2
Output: 5
Explanation: Let's see the rounds of the game:
Round |       arr       | winner | win_count
  1   | [2,1,3,5,4,6,7] | 2      | 1
  2   | [2,3,5,4,6,7,1] | 3      | 1
  3   | [3,5,4,6,7,1,2] | 5      | 1
  4   | [5,4,6,7,1,2,3] | 5      | 2
So we can see that 4 rounds will be played and 5 is the winner because it wins 2 consecutive games.
Example 2:
Input: arr = [3,2,1], k = 10
Output: 3
Explanation: 3 will win the first 10 rounds consecutively.

Constraints:
* 2 <= arr.length <= 105
* 1 <= arr[i] <= 106
* arr contains distinct integers.
* 1 <= k <= 109

*/

let arr = [2, 1, 3, 5, 4, 6, 7];
const k = 2;

// let arr = [3,2,1];
// const k = 10;

let currentWinner;
let winCount = 0;

function verifyResult() {
  if (winCount === k) {
    console.log(`${arr[0]} is the winner`)
    return true;
  }

  return false;
}

function updateArray(a, b) {
  arr = [a, ...arr, b];
  console.log("updateArray", arr);
}

function verifyWinnerAndUpdateWincount(newWinner) {
  if (!currentWinner) {
    currentWinner = newWinner
    winCount++;
    return;
  }
  
  if (currentWinner === newWinner) {
    winCount++;
    return;
  }

  currentWinner = newWinner;
  winCount = 1;
}

function runTests() {
  const a = arr.shift();
  const b = arr.shift();

  if (a > b) {
    console.log(`${a} won`);
    verifyWinnerAndUpdateWincount(a);
    console.log('winCount', winCount)
    updateArray(a, b);

    if (verifyResult()) return;
    return runTests();
  }

  console.log(`${b} won`);
  verifyWinnerAndUpdateWincount(b);
  console.log('winCount', winCount)
  updateArray(b, a);

  if (verifyResult()) return;
  return runTests();
}

console.log(arr)
runTests();