daily

Author: Zanger67

my-submissions/m1718 v1.py

@@ -0,0 +1,45 @@
+class Solution:
+    def helper(self, output: List[int], curr_indx: int, pot_vals: List[int]) -> List[int] | bool :
+        # The check for if there are pot_vals remaining is to check
+        # whether multiple "1"s were used
+        if curr_indx >= len(output) :
+            return output if not pot_vals else False
+
+        if output[curr_indx] :
+            return self.helper(output, curr_indx + 1, pot_vals)
+
+        len_potvals = len(pot_vals)
+        for i in range(len_potvals - 1, -1, -1) :
+            # This part is quite inefficient due to it popping and inserting causing many O(n)
+            # operations but is somewhat needed in order to keep pot_vals sorted when
+            # parsing the potential answers
+            if curr_indx + pot_vals[i] < len(output) and not output[curr_indx + pot_vals[i]] :
+                curr = pot_vals.pop(i)
+                output[curr_indx] = curr
+                output[curr_indx + curr] = curr
+                pot_result = self.helper(output, curr_indx + 1, pot_vals)
+
+                # if returns a list, then answer found
+                # if returns bool FALSE, then invalid case
+                if pot_result :
+                    return output
+
+                pot_vals.insert(i, curr)
+                output[curr_indx] = 0
+                output[curr_indx + curr] = 0
+
+        # Insert the "1" case since it appears once
+        output[curr_indx] = 1
+        pot_result = self.helper(output, curr_indx + 1, pot_vals)
+        if pot_result :
+            return pot_result
+        output[curr_indx] = 0
+
+        return False
+
+
+    def constructDistancedSequence(self, n: int) -> List[int]:
+        output = [0] * (n + n - 1)
+        pot_vals = list(range(2, n + 1))
+
+        return self.helper(output, 0, pot_vals)

my-submissions/m1718 v2.py

@@ -0,0 +1,48 @@
+class Solution:
+    def helper(self, 
+               output: List[int], 
+               curr_indx: int, 
+               pot_vals: List[int], 
+               one_used: bool = False) -> List[int] | bool :
+        if curr_indx >= len(output) :
+            return output
+
+        if output[curr_indx] :
+            return self.helper(output, curr_indx + 1, pot_vals, one_used)
+
+        len_potvals = len(pot_vals)
+        for i in range(len_potvals - 1, -1, -1) :
+            # This part is quite inefficient due to it popping and inserting causing many O(n)
+            # operations but is somewhat needed in order to keep pot_vals sorted when
+            # parsing the potential answers
+            if curr_indx + pot_vals[i] < len(output) and not output[curr_indx + pot_vals[i]] :
+                curr = pot_vals.pop(i)
+                output[curr_indx] = curr
+                output[curr_indx + curr] = curr
+                pot_result = self.helper(output, curr_indx + 1, pot_vals, one_used)
+
+                # if returns a list, then answer found
+                # if returns bool FALSE, then invalid case
+                if pot_result :
+                    return output
+
+                pot_vals.insert(i, curr)
+                output[curr_indx] = 0
+                output[curr_indx + curr] = 0
+
+        # Insert the "1" case since it appears once
+        if not one_used :
+            output[curr_indx] = 1
+            pot_result = self.helper(output, curr_indx + 1, pot_vals, True)
+            if pot_result :
+                return pot_result
+            output[curr_indx] = 0
+
+        return False
+
+
+    def constructDistancedSequence(self, n: int) -> List[int]:
+        output = [0] * (n + n - 1)
+        pot_vals = list(range(2, n + 1))
+
+        return self.helper(output, 0, pot_vals)

my-submissions/m1718.md

@@ -0,0 +1,8 @@
+## V1
+
+## V2
+
+Added a parameter check to see if we've made use of our "1" insert since the prompt
+tells us that it will appear once in the output array. This is in contrast to V1
+where instead we would allow the recursion to fully propogate the OUTPUT array
+and check if any values were unused