function editDistance(source: string, target: string): number {
  // Escribe tu solución aquí
  const a = source.length;
  const b = target.length;

  const dp: number[][] = Array.from({length: a + 1}, () => 
  new Array(b + 1).fill(0));

  for(let i = 0; i <= a; i++) dp[i][0] = i;
  for(let j = 0; j <= b; j++) dp[0][j] = j;

  for (let i = 1; i <= a; i++){
    for (let j = 1; j <= b; j++){
      if(source[i -1] === target[j - 1]){
        dp[i][j] = dp[i - 1][j - 1];
      }else{
        dp[i][j] = 1 + Math.min(
          dp[i - 1][j],
          dp[i][j - 1],
          dp[i - 1][j - 1]
        );

      }
    }
  }

  return dp[a][b];
}

// No modificar: necesario para evaluar el resultado.
export { editDistance };