Add No_1291: Sequential Digits

Author: brianchiang-tw

No_1291_Sequential Digits/No_1291_Sequential Digits_description.md

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+'''
+
+Description:
+
+An integer has sequential digits if and only if each digit in the number is one more than the previous digit.
+
+Return a sorted list of all the integers in the range [low, high] inclusive that have sequential digits.
+
+ 
+
+Example 1:
+
+Input: low = 100, high = 300
+Output: [123,234]
+
+
+
+Example 2:
+
+Input: low = 1000, high = 13000
+Output: [1234,2345,3456,4567,5678,6789,12345]
+ 
+
+Constraints:
+
+10 <= low <= high <= 10^9
+
+'''

No_1291_Sequential Digits/sequential_digits_by_dfs.py

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+'''
+
+Description:
+
+An integer has sequential digits if and only if each digit in the number is one more than the previous digit.
+
+Return a sorted list of all the integers in the range [low, high] inclusive that have sequential digits.
+
+ 
+
+Example 1:
+
+Input: low = 100, high = 300
+Output: [123,234]
+
+
+
+Example 2:
+
+Input: low = 1000, high = 13000
+Output: [1234,2345,3456,4567,5678,6789,12345]
+ 
+
+Constraints:
+
+10 <= low <= high <= 10^9
+
+'''
+
+
+from typing import List
+class Solution:
+    def sequentialDigits(self, low: int, high: int) -> List[int]:
+        
+        
+        output = []
+        
+        digit_stack = list( range(1,10) )
+        
+        while digit_stack:
+            
+            cur_value = digit_stack.pop()
+            
+            if high >= cur_value >= low:
+                output.append( cur_value )
+            
+            elif cur_value > high:
+                # current value is out of boundary
+                # stop growing on this case
+                continue
+            
+            last_digit = int( str(cur_value)[-1] )
+            
+            if last_digit == 9:
+                # last digit is 9 already
+                # stop growing on this case
+                continue
+            
+            growing_value = int( str(cur_value) + str(last_digit+1) )
+            
+            digit_stack.append( growing_value )
+            
+        return sorted( output )
+
+
+
+from collections import namedtuple
+TestEntry = namedtuple('TestEntry', 'lowerbound upperbound')
+def test_bench():
+
+    test_data = [
+                    TestEntry( lowerbound = 100, upperbound = 300),
+                    TestEntry( lowerbound = 1000, upperbound = 13000),
+                    TestEntry( lowerbound = 10, upperbound = 1000000000),
+                ]
+
+    # expected output:
+    '''
+    [123, 234]
+    [1234, 2345, 3456, 4567, 5678, 6789, 12345]
+    [12, 23, 34, 45, 56, 67, 78, 89, 123, 234, 345, 456, 567, 678, 789, 1234, 2345, 3456, 4567, 5678, 6789, 12345, 23456, 34567, 45678, 56789, 123456, 234567, 345678, 456789, 1234567, 2345678, 3456789, 12345678, 23456789, 123456789]    
+    '''
+
+
+    for t in test_data:
+
+        print( Solution().sequentialDigits( low = t.lowerbound, high = t.upperbound) )
+
+    return
+
+
+
+if __name__ == '__main__':
+
+    test_bench()