Calculate Amount Paid in Taxes LeetCode solution in JavaScript

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var calculateTax = function (brackets, income) {
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  return brackets.reduce(
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    ([tax, prev], [upper, percent]) => {
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      let curr = Math.min(income, upper - prev);
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      tax += curr * (percent / 100);
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      income -= curr;
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      if (income <= 0) brackets.length = 0;
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      return [tax, upper];
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    },
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    [0, 0]
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  )[0];
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};