dluciano

public class Solution {
  public string MakeGood(string s) {
      if(s.Length <= 1) 
        return s;
      var sb = new StringBuilder(s);
      var i = 1;
      while(i < sb.Length){
        if(Math.Abs(sb[i] - sb[i - 1]) ==  ('a' - 'A')){
          sb.Remove(i, 1);
          sb.Remove(i - 1, 1);

dluciano

public class Solution {
  public int Maximum69Number (int num) {
    var numBase = (int)Math.Log(num, 10);
    var div = (int)Math.Pow(10, numBase);
    var maxNumber = 0;
    var flipped = false;
    while(num > 0){
      var digit = num / div;
      num = num - (digit * div);
      if(digit == 6 && !flipped){

dluciano

public class Solution {
  public string AddBoldTag(string s, string[] words) {
    BitArray FindMatches(){
      var i = 0;
      var bits = new BitArray(s.Length);
      while(i < s.Length){
        foreach(var word in words){
          if(i + word.Length > s.Length)            
            continue;
          var k = i;

dluciano

public class Solution {
  private readonly List<string> _result = new();
  
  public IList<string> FindWords(char[][] board, string[] words) {
    var root = CreateTrie(words);
    FindWords(board, root);
    return _result;
  }
  
  static readonly (int row, int col)[] directions = new (int row, int col)[]{

dluciano

public class Solution {
  public int LongestPalindrome(string[] words) {
    var freq = new Dictionary<string, int>();
    var palindromes = new HashSet<string>();
    var counter = 0;

    foreach(var word in words){
      if(!freq.ContainsKey(word))
        freq[word] = 0;
      freq[word]++;

dluciano

public class Solution {
  public int MinMutation(string start, string end, string[] bank) {
    var q = new Queue<string>();
    var visited = new HashSet<string>();
    var minMutation = 0;

    q.Enqueue(start);
    
    while(q.Count > 0){
      var sz = q.Count;

dluciano

public class Solution {
  public int SmallestCommonElement(int[][] mat) {
    var cursors = new int[mat.Length];
    var ROWS = mat.Length;
    var COLS = mat[0].Length;
    while(true){
      var row = 0;
      var allFound = true;
      var min = -1;
      while(row + 1 < ROWS){

dluciano

public class Solution {
  public int[] FindBall(int[][] grid) {
    var ROWS = grid.Length;
    var COLS = grid[0].Length;
    var result = new int[COLS];
    // [ball_id, ball_pos]
    var balls = new Queue<int[]>();
    
    for(var col = 0; col < COLS; ++col)
      balls.Enqueue(new int[]{ col, col });

dluciano

public class Solution {
  public bool IsToeplitzMatrix(int[][] matrix) {
    var ROWS = matrix.Length;
    var COLS = matrix[0].Length;
    for(var col = 0; col < COLS; ++col)
      if(!IsEqualDiagonal(0, col, matrix))
        return false;
    
    for(var row = 0; row < ROWS; ++row)
      if(!IsEqualDiagonal(row, 0, matrix))

dluciano

public class Solution {
  public IList<IList<string>> GroupAnagrams(string[] strs) {
    var groups = new List<IList<string>>();
    var dict = new Dictionary<string, List<string>>();
    
    string KeyForWord(in string word){
      var freq = Freq(word);
      var sb = new StringBuilder();
      for(var c = 0; c < freq.Length; ++c)
        sb.Append($"{c}-{freq[c]},");