Minimum Time to Finish the Race LeetCode solution in JavaScript

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var minimumFinishTime = function (tires, changeTime, numLaps) {
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  const n = tires.length;
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  const smallestTire = Math.min(...tires.map((t) => t[1]));
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  const maxSameTire =
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    Math.floor(Math.log(changeTime) / Math.log(smallestTire)) + 1;
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  const sameTireLast = Array(n).fill(0);
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  // DP array tracking what is the min cost to complete lap i using same tire
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  const sameTire = Array(maxSameTire + 1).fill(Infinity);
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  for (let lap = 1; lap <= maxSameTire; lap++) {
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    tires.forEach((tire, i) => {
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      sameTireLast[i] += tire[0] * tire[1] ** (lap - 1);
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      sameTire[lap] = Math.min(sameTire[lap], sameTireLast[i]);
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    });
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  }
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  const dp = Array(numLaps + 1).fill(Infinity);
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  for (let i = 1; i < numLaps + 1; i++) {
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    if (i <= maxSameTire) dp[i] = sameTire[i];
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    // at each lap, we can either use the same tire up to this lap (sameTire[i])
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    // or a combination of 2 different best times,
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    // eg lap 6: use best time from lap 3 + lap 3
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    // or from lap 4 + lap 2
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    // or lap 5 + lap 1
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    for (let j = 1; j < i / 2 + 1; j++) {
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      dp[i] = Math.min(dp[i], dp[i - j] + changeTime + dp[j]);
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    }
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  }
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  return dp[numLaps];
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};