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스테핑 번호

GfG Practice에서 사용해 보세요. ' title= #practiceLinkDiv { 표시: 없음 !중요; }

두 개의 정수 'n'과 'm'이 주어지면 [n·m] 범위의 모든 스테핑 숫자를 찾습니다. 번호가 불려요 스테핑 번호 인접한 모든 숫자의 절대 차이가 1인 경우 321은 스테핑 번호이고 421은 그렇지 않습니다.

예: 



  Input :   n = 0 m = 21   Output :   0 1 2 3 4 5 6 7 8 9 10 12 21   Input :   n = 10 m = 15   Output :   10 12
Recommended Practice 하나의 절대적인 차이가 있는 숫자 시도해 보세요!

방법 1: 무차별 접근 방식
이 방법에서는 무차별 접근 방식을 사용하여 n부터 m까지의 모든 정수를 반복하고 그것이 스테핑 번호인지 확인합니다. 

C++
// A C++ program to find all the Stepping Number in [n m] #include   using namespace std; // This function checks if an integer n is a Stepping Number bool isStepNum(int n) {  // Initialize prevDigit with -1  int prevDigit = -1;  // Iterate through all digits of n and compare difference  // between value of previous and current digits  while (n)  {  // Get Current digit  int curDigit = n % 10;  // Single digit is consider as a  // Stepping Number  if (prevDigit == -1)  prevDigit = curDigit;  else  {  // Check if absolute difference between  // prev digit and current digit is 1  if (abs(prevDigit - curDigit) != 1)  return false;  }  prevDigit = curDigit;  n /= 10;  }  return true; } // A brute force approach based function to find all // stepping numbers. void displaySteppingNumbers(int n int m) {  // Iterate through all the numbers from [NM]  // and check if it’s a stepping number.  for (int i=n; i<=m; i++)  if (isStepNum(i))  cout << i << ' '; } // Driver program to test above function int main() {  int n = 0 m = 21;  // Display Stepping Numbers in  // the range [n m]  displaySteppingNumbers(n m);  return 0; } 
Java
// A Java program to find all the Stepping Number in [n m] class Main {  // This Method checks if an integer n  // is a Stepping Number  public static boolean isStepNum(int n)  {  // Initialize prevDigit with -1  int prevDigit = -1;  // Iterate through all digits of n and compare  // difference between value of previous and  // current digits  while (n > 0)  {  // Get Current digit  int curDigit = n % 10;  // Single digit is consider as a  // Stepping Number  if (prevDigit != -1)  {  // Check if absolute difference between  // prev digit and current digit is 1  if (Math.abs(curDigit-prevDigit) != 1)  return false;  }  n /= 10;  prevDigit = curDigit;  }  return true;  }  // A brute force approach based function to find all  // stepping numbers.  public static void displaySteppingNumbers(int nint m)  {  // Iterate through all the numbers from [NM]  // and check if it is a stepping number.  for (int i = n; i <= m; i++)  if (isStepNum(i))  System.out.print(i+ ' ');  }  // Driver code  public static void main(String args[])  {  int n = 0 m = 21;  // Display Stepping Numbers in the range [nm]  displaySteppingNumbers(nm);  } } 
Python3
# A Python3 program to find all the Stepping Number in [n m] # This function checks if an integer n is a Stepping Number def isStepNum(n): # Initialize prevDigit with -1 prevDigit = -1 # Iterate through all digits of n and compare difference # between value of previous and current digits while (n): # Get Current digit curDigit = n % 10 # Single digit is consider as a # Stepping Number if (prevDigit == -1): prevDigit = curDigit else: # Check if absolute difference between # prev digit and current digit is 1 if (abs(prevDigit - curDigit) != 1): return False prevDigit = curDigit n //= 10 return True # A brute force approach based function to find all # stepping numbers. def displaySteppingNumbers(n m): # Iterate through all the numbers from [NM] # and check if it’s a stepping number. for i in range(n m + 1): if (isStepNum(i)): print(i end = ' ') # Driver code if __name__ == '__main__': n m = 0 21 # Display Stepping Numbers in # the range [n m] displaySteppingNumbers(n m) # This code is contributed by mohit kumar 29 
C#
// A C# program to find all  // the Stepping Number in [n m] using System; class GFG {  // This Method checks if an   // integer n is a Stepping Number  public static bool isStepNum(int n)  {  // Initialize prevDigit with -1  int prevDigit = -1;  // Iterate through all digits   // of n and compare difference   // between value of previous   // and current digits  while (n > 0)  {  // Get Current digit  int curDigit = n % 10;  // Single digit is considered   // as a Stepping Number  if (prevDigit != -1)  {  // Check if absolute difference   // between prev digit and current   // digit is 1  if (Math.Abs(curDigit -   prevDigit) != 1)  return false;  }  n /= 10;  prevDigit = curDigit;  }  return true;  }  // A brute force approach based   // function to find all stepping numbers.  public static void displaySteppingNumbers(int n   int m)  {  // Iterate through all the numbers   // from [NM] and check if it is   // a stepping number.  for (int i = n; i <= m; i++)  if (isStepNum(i))  Console.Write(i+ ' ');  }  // Driver code  public static void Main()  {  int n = 0 m = 21;  // Display Stepping Numbers   // in the range [nm]  displaySteppingNumbers(n m);  } } // This code is contributed by nitin mittal. 
JavaScript
<script>  // A Javascript program to find all the Stepping Number in [n m]    // This function checks if an integer n is a Stepping Number  function isStepNum(n)  {  // Initialize prevDigit with -1  let prevDigit = -1;  // Iterate through all digits of n and compare difference  // between value of previous and current digits  while (n > 0)  {  // Get Current digit  let curDigit = n % 10;  // Single digit is consider as a  // Stepping Number  if (prevDigit == -1)  prevDigit = curDigit;  else  {  // Check if absolute difference between  // prev digit and current digit is 1  if (Math.abs(prevDigit - curDigit) != 1)  return false;  }  prevDigit = curDigit;  n = parseInt(n / 10 10);  }  return true;  }  // A brute force approach based function to find all  // stepping numbers.  function displaySteppingNumbers(n m)  {  // Iterate through all the numbers from [NM]  // and check if it’s a stepping number.  for (let i = n; i <= m; i++)  if (isStepNum(i))  document.write(i + ' ');  }  let n = 0 m = 21;    // Display Stepping Numbers in  // the range [n m]  displaySteppingNumbers(n m);    // This code is contributed by mukesh07. </script> 

산출
0 1 2 3 4 5 6 7 8 9 10 12 21 

방법 2: BFS/DFS 사용

클래스가 여러 클래스를 확장할 수 있나요?

아이디어는 너비 우선 검색 / 깊이 우선 검색 순회.



그래프를 작성하는 방법은 무엇입니까?  
그래프의 모든 노드는 스테핑 번호를 나타냅니다. V가 U에서 변환될 수 있는 경우 노드 U에서 V로 방향이 지정된 에지가 있을 것입니다. (U와 V는 스테핑 번호입니다.) 스테핑 번호 V는 다음과 같은 방식으로 U에서 변환될 수 있습니다.
마지막 숫자 U의 마지막 숫자를 나타냅니다(예: U % 10). 
인접한 숫자 다섯 다음과 같을 수 있습니다:  

  • U*10 + lastDigit + 1(이웃 A)
  • U*10 + lastDigit – 1 (이웃 B)


위의 연산을 적용하면 새 숫자가 U에 추가됩니다. 이는 lastDigit-1 또는 lastDigit+1이므로 U에서 형성된 새 숫자 V도 스테핑 번호입니다. 
따라서 모든 노드에는 최대 2개의 인접 노드가 있습니다.
엣지 케이스: U의 마지막 숫자가 또는 9

가장 아름다운 미소
    사례 1:lastDigit is 0 : 이 경우 숫자 '1'만 추가할 수 있습니다.사례 2:lastDigit is 9 : 이 경우 숫자 '8'만 추가할 수 있습니다.

소스/시작 노드는 무엇입니까?   



  • 모든 단일 숫자는 스테핑 번호로 간주되므로 모든 숫자에 대한 bfs 순회는 해당 숫자에서 시작하는 모든 스테핑 번호를 제공합니다.
  • [09]의 모든 숫자에 대해 bfs/dfs 순회를 수행합니다.

메모: 노드 0의 경우 BFS 순회 중에 이웃을 탐색할 필요가 없습니다. 왜냐하면 01 012 010으로 연결되고 노드 1부터 시작하는 BFS 순회에 의해 다루어지기 때문입니다. 
0부터 21까지의 모든 스테핑 번호를 찾는 예   

-> 0 is a stepping Number and it is in the range so display it. -> 1 is a Stepping Number find neighbors of 1 i.e. 10 and 12 and push them into the queue   How to get 10 and 12?   Here U is 1 and last Digit is also 1 V = 10 + 0 = 10 ( Adding lastDigit - 1 ) V = 10 + 2 = 12 ( Adding lastDigit + 1 ) Then do the same for 10 and 12 this will result into 101 123 121 but these Numbers are out of range. Now any number transformed from 10 and 12 will result into a number greater than 21 so no need to explore their neighbors. -> 2 is a Stepping Number find neighbors of 2 i.e. 21 23. -> 23 is out of range so it is not considered as a Stepping Number (Or a neighbor of 2) The other stepping numbers will be 3 4 5 6 7 8 9.

BFS 기반 솔루션:

C++
// A C++ program to find all the Stepping Number from N=n // to m using BFS Approach #include   using namespace std; // Prints all stepping numbers reachable from num // and in range [n m] void bfs(int n int m int num) {  // Queue will contain all the stepping Numbers  queue<int> q;  q.push(num);  while (!q.empty())  {  // Get the front element and pop from the queue  int stepNum = q.front();  q.pop();  // If the Stepping Number is in the range  // [n m] then display  if (stepNum <= m && stepNum >= n)  cout << stepNum << ' ';  // If Stepping Number is 0 or greater than m  // no need to explore the neighbors  if (num == 0 || stepNum > m)  continue;  // Get the last digit of the currently visited  // Stepping Number  int lastDigit = stepNum % 10;  // There can be 2 cases either digit to be  // appended is lastDigit + 1 or lastDigit - 1  int stepNumA = stepNum * 10 + (lastDigit- 1);  int stepNumB = stepNum * 10 + (lastDigit + 1);  // If lastDigit is 0 then only possible digit  // after 0 can be 1 for a Stepping Number  if (lastDigit == 0)  q.push(stepNumB);  //If lastDigit is 9 then only possible  //digit after 9 can be 8 for a Stepping  //Number  else if (lastDigit == 9)  q.push(stepNumA);  else  {  q.push(stepNumA);  q.push(stepNumB);  }  } } // Prints all stepping numbers in range [n m] // using BFS. void displaySteppingNumbers(int n int m) {  // For every single digit Number 'i'  // find all the Stepping Numbers  // starting with i  for (int i = 0 ; i <= 9 ; i++)  bfs(n m i); } //Driver program to test above function int main() {  int n = 0 m = 21;  // Display Stepping Numbers in the  // range [nm]  displaySteppingNumbers(nm);  return 0; } 
Java
// A Java program to find all the Stepping Number in // range [n m] import java.util.*; class Main {  // Prints all stepping numbers reachable from num  // and in range [n m]  public static void bfs(int nint mint num)  {  // Queue will contain all the stepping Numbers  Queue<Integer> q = new LinkedList<Integer> ();  q.add(num);  while (!q.isEmpty())  {  // Get the front element and pop from  // the queue  int stepNum = q.poll();  // If the Stepping Number is in  // the range [nm] then display  if (stepNum <= m && stepNum >= n)  {  System.out.print(stepNum + ' ');  }  // If Stepping Number is 0 or greater  // then m no need to explore the neighbors  if (stepNum == 0 || stepNum > m)  continue;  // Get the last digit of the currently  // visited Stepping Number  int lastDigit = stepNum % 10;  // There can be 2 cases either digit  // to be appended is lastDigit + 1 or  // lastDigit - 1  int stepNumA = stepNum * 10 + (lastDigit- 1);  int stepNumB = stepNum * 10 + (lastDigit + 1);  // If lastDigit is 0 then only possible  // digit after 0 can be 1 for a Stepping  // Number  if (lastDigit == 0)  q.add(stepNumB);  // If lastDigit is 9 then only possible  // digit after 9 can be 8 for a Stepping  // Number  else if (lastDigit == 9)  q.add(stepNumA);  else  {  q.add(stepNumA);  q.add(stepNumB);  }  }  }  // Prints all stepping numbers in range [n m]  // using BFS.  public static void displaySteppingNumbers(int nint m)  {  // For every single digit Number 'i'  // find all the Stepping Numbers  // starting with i  for (int i = 0 ; i <= 9 ; i++)  bfs(n m i);  }  //Driver code  public static void main(String args[])  {  int n = 0 m = 21;  // Display Stepping Numbers in  // the range [nm]  displaySteppingNumbers(nm);  } } 
Python3
# A Python3 program to find all the Stepping Number from N=n # to m using BFS Approach # Prints all stepping numbers reachable from num # and in range [n m] def bfs(n m num) : # Queue will contain all the stepping Numbers q = [] q.append(num) while len(q) > 0 : # Get the front element and pop from the queue stepNum = q[0] q.pop(0); # If the Stepping Number is in the range # [n m] then display if (stepNum <= m and stepNum >= n) : print(stepNum end = ' ') # If Stepping Number is 0 or greater than m # no need to explore the neighbors if (num == 0 or stepNum > m) : continue # Get the last digit of the currently visited # Stepping Number lastDigit = stepNum % 10 # There can be 2 cases either digit to be # appended is lastDigit + 1 or lastDigit - 1 stepNumA = stepNum * 10 + (lastDigit- 1) stepNumB = stepNum * 10 + (lastDigit + 1) # If lastDigit is 0 then only possible digit # after 0 can be 1 for a Stepping Number if (lastDigit == 0) : q.append(stepNumB) #If lastDigit is 9 then only possible #digit after 9 can be 8 for a Stepping #Number elif (lastDigit == 9) : q.append(stepNumA) else : q.append(stepNumA) q.append(stepNumB) # Prints all stepping numbers in range [n m] # using BFS. def displaySteppingNumbers(n m) : # For every single digit Number 'i' # find all the Stepping Numbers # starting with i for i in range(10) : bfs(n m i) # Driver code n m = 0 21 # Display Stepping Numbers in the # range [nm] displaySteppingNumbers(n m) # This code is contributed by divyeshrabadiya07. 
C#
// A C# program to find all the Stepping Number in // range [n m] using System; using System.Collections.Generic; public class GFG {    // Prints all stepping numbers reachable from num  // and in range [n m]  static void bfs(int n int m int num)  {    // Queue will contain all the stepping Numbers  Queue<int> q = new Queue<int>();  q.Enqueue(num);  while(q.Count != 0)  {    // Get the front element and pop from  // the queue  int stepNum = q.Dequeue();    // If the Stepping Number is in  // the range [nm] then display  if (stepNum <= m && stepNum >= n)  {  Console.Write(stepNum + ' ');  }    // If Stepping Number is 0 or greater  // then m no need to explore the neighbors  if (stepNum == 0 || stepNum > m)  continue;    // Get the last digit of the currently  // visited Stepping Number  int lastDigit = stepNum % 10;    // There can be 2 cases either digit  // to be appended is lastDigit + 1 or  // lastDigit - 1  int stepNumA = stepNum * 10 + (lastDigit- 1);  int stepNumB = stepNum * 10 + (lastDigit + 1);    // If lastDigit is 0 then only possible  // digit after 0 can be 1 for a Stepping  // Number  if (lastDigit == 0)  q.Enqueue(stepNumB);    // If lastDigit is 9 then only possible  // digit after 9 can be 8 for a Stepping  // Number  else if (lastDigit == 9)  q.Enqueue(stepNumA);  else  {  q.Enqueue(stepNumA);  q.Enqueue(stepNumB);  }  }  }    // Prints all stepping numbers in range [n m]  // using BFS.  static void displaySteppingNumbers(int nint m)  {  // For every single digit Number 'i'  // find all the Stepping Numbers  // starting with i  for (int i = 0 ; i <= 9 ; i++)  bfs(n m i);  }    // Driver code  static public void Main ()  {  int n = 0 m = 21;    // Display Stepping Numbers in  // the range [nm]  displaySteppingNumbers(nm);  } } // This code is contributed by avanitrachhadiya2155 
JavaScript
<script> // A Javascript program to find all // the Stepping Number in // range [n m]    // Prints all stepping numbers   // reachable from num  // and in range [n m]  function bfs(nmnum)  {  // Queue will contain all the   // stepping Numbers  let q = [];    q.push(num);    while (q.length!=0)  {  // Get the front element and pop from  // the queue  let stepNum = q.shift();    // If the Stepping Number is in  // the range [nm] then display  if (stepNum <= m && stepNum >= n)  {  document.write(stepNum + ' ');  }    // If Stepping Number is 0 or greater  // then m no need to explore the neighbors  if (stepNum == 0 || stepNum > m)  continue;    // Get the last digit of the currently  // visited Stepping Number  let lastDigit = stepNum % 10;    // There can be 2 cases either digit  // to be appended is lastDigit + 1 or  // lastDigit - 1  let stepNumA = stepNum * 10 + (lastDigit- 1);  let stepNumB = stepNum * 10 + (lastDigit + 1);    // If lastDigit is 0 then only possible  // digit after 0 can be 1 for a Stepping  // Number  if (lastDigit == 0)  q.push(stepNumB);    // If lastDigit is 9 then only possible  // digit after 9 can be 8 for a Stepping  // Number  else if (lastDigit == 9)  q.push(stepNumA);    else  {  q.push(stepNumA);  q.push(stepNumB);  }  }  }    // Prints all stepping numbers in range [n m]  // using BFS.  function displaySteppingNumbers(nm)  {  // For every single digit Number 'i'  // find all the Stepping Numbers  // starting with i  for (let i = 0 ; i <= 9 ; i++)  bfs(n m i);  }      // Driver code  let n = 0 m = 21;    // Display Stepping Numbers in  // the range [nm]  displaySteppingNumbers(nm);      // This code is contributed by unknown2108   </script> 

산출
0 1 10 12 2 21 3 4 5 6 7 8 9 

DFS 기반 솔루션:

Git에서 체크아웃
C++
// A C++ program to find all the Stepping Numbers // in range [n m] using DFS Approach #include   using namespace std; // Prints all stepping numbers reachable from num // and in range [n m] void dfs(int n int m int stepNum) {  // If Stepping Number is in the  // range [nm] then display  if (stepNum <= m && stepNum >= n)  cout << stepNum << ' ';  // If Stepping Number is 0 or greater  // than m then return  if (stepNum == 0 || stepNum > m)  return ;  // Get the last digit of the currently  // visited Stepping Number  int lastDigit = stepNum % 10;  // There can be 2 cases either digit  // to be appended is lastDigit + 1 or  // lastDigit - 1  int stepNumA = stepNum*10 + (lastDigit-1);  int stepNumB = stepNum*10 + (lastDigit+1);  // If lastDigit is 0 then only possible  // digit after 0 can be 1 for a Stepping  // Number  if (lastDigit == 0)  dfs(n m stepNumB);  // If lastDigit is 9 then only possible  // digit after 9 can be 8 for a Stepping  // Number  else if(lastDigit == 9)  dfs(n m stepNumA);  else  {  dfs(n m stepNumA);  dfs(n m stepNumB);  } } // Method displays all the stepping // numbers in range [n m] void displaySteppingNumbers(int n int m) {  // For every single digit Number 'i'  // find all the Stepping Numbers  // starting with i  for (int i = 0 ; i <= 9 ; i++)  dfs(n m i); } //Driver program to test above function int main() {  int n = 0 m = 21;  // Display Stepping Numbers in  // the range [nm]  displaySteppingNumbers(nm);  return 0; } 
Java
// A Java program to find all the Stepping Numbers // in range [n m] using DFS Approach import java.util.*; class Main {  // Method display's all the stepping numbers  // in range [n m]  public static void dfs(int nint mint stepNum)  {  // If Stepping Number is in the  // range [nm] then display  if (stepNum <= m && stepNum >= n)  System.out.print(stepNum + ' ');  // If Stepping Number is 0 or greater  // than m then return  if (stepNum == 0 || stepNum > m)  return ;  // Get the last digit of the currently  // visited Stepping Number  int lastDigit = stepNum % 10;  // There can be 2 cases either digit  // to be appended is lastDigit + 1 or  // lastDigit - 1  int stepNumA = stepNum*10 + (lastDigit-1);  int stepNumB = stepNum*10 + (lastDigit+1);  // If lastDigit is 0 then only possible  // digit after 0 can be 1 for a Stepping  // Number  if (lastDigit == 0)  dfs(n m stepNumB);  // If lastDigit is 9 then only possible  // digit after 9 can be 8 for a Stepping  // Number  else if(lastDigit == 9)  dfs(n m stepNumA);  else  {  dfs(n m stepNumA);  dfs(n m stepNumB);  }  }  // Prints all stepping numbers in range [n m]  // using DFS.  public static void displaySteppingNumbers(int n int m)  {  // For every single digit Number 'i'  // find all the Stepping Numbers  // starting with i  for (int i = 0 ; i <= 9 ; i++)  dfs(n m i);  }  // Driver code  public static void main(String args[])  {  int n = 0 m = 21;  // Display Stepping Numbers in  // the range [nm]  displaySteppingNumbers(nm);  } } 
Python3
# A Python3 program to find all the Stepping Numbers # in range [n m] using DFS Approach # Prints all stepping numbers reachable from num # and in range [n m] def dfs(n m stepNum) : # If Stepping Number is in the # range [nm] then display if (stepNum <= m and stepNum >= n) : print(stepNum end = ' ') # If Stepping Number is 0 or greater # than m then return if (stepNum == 0 or stepNum > m) : return # Get the last digit of the currently # visited Stepping Number lastDigit = stepNum % 10 # There can be 2 cases either digit # to be appended is lastDigit + 1 or # lastDigit - 1 stepNumA = stepNum * 10 + (lastDigit - 1) stepNumB = stepNum * 10 + (lastDigit + 1) # If lastDigit is 0 then only possible # digit after 0 can be 1 for a Stepping # Number if (lastDigit == 0) : dfs(n m stepNumB) # If lastDigit is 9 then only possible # digit after 9 can be 8 for a Stepping # Number elif(lastDigit == 9) : dfs(n m stepNumA) else : dfs(n m stepNumA) dfs(n m stepNumB) # Method displays all the stepping # numbers in range [n m] def displaySteppingNumbers(n m) : # For every single digit Number 'i' # find all the Stepping Numbers # starting with i for i in range(10) : dfs(n m i) n m = 0 21 # Display Stepping Numbers in # the range [nm] displaySteppingNumbers(n m) # This code is contributed by divyesh072019. 
C#
// A C# program to find all the Stepping Numbers // in range [n m] using DFS Approach using System; public class GFG {  // Method display's all the stepping numbers  // in range [n m]  static void dfs(int n int m int stepNum)  {  // If Stepping Number is in the  // range [nm] then display  if (stepNum <= m && stepNum >= n)  Console.Write(stepNum + ' ');  // If Stepping Number is 0 or greater  // than m then return  if (stepNum == 0 || stepNum > m)  return ;  // Get the last digit of the currently  // visited Stepping Number  int lastDigit = stepNum % 10;  // There can be 2 cases either digit  // to be appended is lastDigit + 1 or  // lastDigit - 1  int stepNumA = stepNum*10 + (lastDigit - 1);  int stepNumB = stepNum*10 + (lastDigit + 1);  // If lastDigit is 0 then only possible  // digit after 0 can be 1 for a Stepping  // Number  if (lastDigit == 0)  dfs(n m stepNumB);  // If lastDigit is 9 then only possible  // digit after 9 can be 8 for a Stepping  // Number  else if(lastDigit == 9)  dfs(n m stepNumA);  else  {  dfs(n m stepNumA);  dfs(n m stepNumB);  }  }  // Prints all stepping numbers in range [n m]  // using DFS.  public static void displaySteppingNumbers(int n int m)  {  // For every single digit Number 'i'  // find all the Stepping Numbers  // starting with i  for (int i = 0 ; i <= 9 ; i++)  dfs(n m i);  }  // Driver code  static public void Main ()  {  int n = 0 m = 21;  // Display Stepping Numbers in  // the range [nm]  displaySteppingNumbers(nm);  } } // This code is contributed by rag2127. 
JavaScript
<script> // A Javascript program to find all the Stepping Numbers // in range [n m] using DFS Approach // Method display's all the stepping numbers  // in range [n m] function dfs(n m stepNum) {  // If Stepping Number is in the  // range [nm] then display  if (stepNum <= m && stepNum >= n)  document.write(stepNum + ' ');    // If Stepping Number is 0 or greater  // than m then return  if (stepNum == 0 || stepNum > m)  return ;    // Get the last digit of the currently  // visited Stepping Number  let lastDigit = stepNum % 10;    // There can be 2 cases either digit  // to be appended is lastDigit + 1 or  // lastDigit - 1  let stepNumA = stepNum*10 + (lastDigit-1);  let stepNumB = stepNum*10 + (lastDigit+1);    // If lastDigit is 0 then only possible  // digit after 0 can be 1 for a Stepping  // Number  if (lastDigit == 0)  dfs(n m stepNumB);    // If lastDigit is 9 then only possible  // digit after 9 can be 8 for a Stepping  // Number  else if(lastDigit == 9)  dfs(n m stepNumA);  else  {  dfs(n m stepNumA);  dfs(n m stepNumB);  } } // Prints all stepping numbers in range [n m]  // using DFS. function displaySteppingNumbers(n m) {  // For every single digit Number 'i'  // find all the Stepping Numbers  // starting with i  for (let i = 0 ; i <= 9 ; i++)  dfs(n m i); } // Driver code let n = 0 m = 21;   // Display Stepping Numbers in // the range [nm] displaySteppingNumbers(nm); // This code is contributed by ab2127 </script> 

산출
0 1 10 12 2 21 3 4 5 6 7 8 9 

시간 복잡도:O(N log N)

공간 복잡도:O(N) 여기서 N은 범위 내의 스테핑 번호 수입니다.