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/*Copyright (c) 2011 Andrei Mackenzie
Permission is hereby granted, free of charge, to any person obtaining a copy ofthis software and associated documentation files (the "Software"), to deal inthe Software without restriction, including without limitation the rights touse, copy, modify, merge, publish, distribute, sublicense, and/or sell copies ofthe Software, and to permit persons to whom the Software is furnished to do so,subject to the following conditions:
The above copyright notice and this permission notice shall be included in allcopies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS ORIMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESSFOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS ORCOPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHERIN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR INCONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.*/
// levenshtein distance algorithm, pulled from Andrei Mackenzie's MIT licensed.// gist, which can be found here: https://gist.github.com/andrei-m/982927// extended to compute damerau-levenshtein distance
// Compute the edit distance between the two given stringsexport function levenshtein(a: string, b: string) {  if (a.length === 0) return b.length;  if (b.length === 0) return a.length;
  const matrix = [];
  // increment along the first column of each row  let i;  for (i = 0; i <= b.length; i++) {    matrix[i] = [i];  }
  // increment each column in the first row  let j;  for (j = 0; j <= a.length; j++) {    matrix[0][j] = j;  }
  // Fill in the rest of the matrix  for (i = 1; i <= b.length; i++) {    for (j = 1; j <= a.length; j++) {      if (b.charAt(i - 1) === a.charAt(j - 1)) {        matrix[i][j] = matrix[i - 1][j - 1];      } else {        if (          i > 1 &&          j > 1 &&          b.charAt(i - 2) === a.charAt(j - 1) &&          b.charAt(i - 1) === a.charAt(j - 2)        ) {          matrix[i][j] = matrix[i - 2][j - 2] + 1; // transposition        } else {          matrix[i][j] = Math.min(            matrix[i - 1][j - 1] + 1, // substitution            Math.min(              matrix[i][j - 1] + 1, // insertion              matrix[i - 1][j] + 1            )          ); // deletion        }      }    }  }
  return matrix[b.length][a.length];}