comefrom: <awangdev>Cracking the Safe_2.java
code: private void dfs(int n, int k, double total, Set<String> visited, StringBuffer sb) {
  
          if (visited.size() == total) return;
          String tail = sb.substring(sb.length() - n + 1);
          for (int j = k - 1; j >= 0; j--) {
              String newStr = tail + j;
              if (visited.contains(newStr)) continue;
              visited.add(newStr);
              sb.append(j);
              dfs(n, k, total, visited, sb);
          }
      }
masked: private void sample_funcname ( int n , int k , double total , Set < String > visited , StringBuffer sb ) {
    if ( visited . size ( ) == total ) return ;
    String tail = sb . substring ( sb . length ( ) - n + 1 ) ;
    for ( int j = k - 1 ;
    j >= 0 ;
    j -- ) {
      String newStr = tail + j ;
      if ( visited . contains ( newStr ) ) continue ;
      visited . add ( newStr ) ;
      sb . append ( j ) ;
      dfs ( n , k , total , visited , sb ) ;
    }
  }
  