Minimum Deletions to Make Character Frequencies Unique LeetCode solution in JavaScript

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var minDeletions = function (s) {
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  let freq = new Array(26).fill(0); // Create an array to store character frequencies
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  for (let i = 0; i < s.length; i++) {
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    freq[s.charCodeAt(i) - "a".charCodeAt(0)]++; // Count the frequency of each character
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  }
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  freq.sort((a, b) => a - b); // Sort frequencies in ascending order
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  let del = 0; // Initialize the deletion count
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  for (let i = 24; i >= 0; i--) {
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    if (freq[i] === 0) {
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      break; // No more characters with this frequency
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    }
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    if (freq[i] >= freq[i + 1]) {
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      let prev = freq[i];
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      freq[i] = Math.max(0, freq[i + 1] - 1);
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      del += prev - freq[i]; // Update the deletion count
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    }
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  }
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  return del; // Return the minimum deletions required
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};