All Divisions With the Highest Score of a Binary Array LeetCode solution in JavaScript

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/**
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 * @param {number[]} nums
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 * @return {number[]}
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 */
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var maxScoreIndices = function (nums) {
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  let n = nums.length;
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  // initialize 3 arrays for counting with n+1 size
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  let zeros = new Array(n + 1).fill(0);
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  let ones = new Array(n + 1).fill(0);
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  let total = new Array(n + 1).fill(0);
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  // count no of zeros from left to right
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  for (let i = 0; i < n; i++) {
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    if (nums[i] == 0) zeros[i + 1] = zeros[i] + 1;
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    else zeros[i + 1] = zeros[i];
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  }
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  // count no of ones from right to left
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  for (let i = n - 1; i >= 0; i--) {
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    if (nums[i] == 1) ones[i] = ones[i + 1] + 1;
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    else ones[i] = ones[i + 1];
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  }
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  // merge left and right to total and find max element
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  let max = 0;
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  for (let i = 0; i < n + 1; i++) {
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    total[i] = ones[i] + zeros[i];
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    if (total[i] > max) max = total[i];
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  }
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  // Find occurrence of max elements and return those indexes
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  let ans = [];
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  for (let i = 0; i < n + 1; i++) {
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    if (total[i] == max) ans.push(i);
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  }
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  return ans;
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};