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var maxProfit = function (A, k) {
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  //rangeSum Formula
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  let rangesum = (i, j) => {
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    (i = BigInt(i)), (j = BigInt(j));
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    return (j * (j + 1n)) / 2n - (i * (i + 1n)) / 2n;
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  };
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  A.unshift(0); //prepend the sentinel 0
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  A.sort((a, b) => a - b);
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  let n = A.length,
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    result = 0n,
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    mod = BigInt(1e9 + 7),
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    i = n - 1;
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  // can use all current levels
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  while (k >= (n - i) * (A[i] - A[i - 1]) && i > 0) {
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    if (A[i] != A[i - 1])
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      (result = (result + rangesum(A[i - 1], A[i]) * BigInt(n - i)) % mod),
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        (k -= (n - i) * (A[i] - A[i - 1]));
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    i--;
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  }
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  //can use some of the current levels
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  if (k > 0 && k >= n - i) {
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    let levels = Math.floor(k / (n - i)); //the levels i can use
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    result = (result + BigInt(n - i) * rangesum(A[i] - levels, A[i])) % mod;
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    k -= levels * (n - i);
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    A[i] -= levels;
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  }
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  // can use some of the items OF the first level
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  if (k > 0 && k < n - i) result = (result + BigInt(k) * BigInt(A[i])) % mod;
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  return Number(result);
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};