Leetcode maxConcatString

Author: Vic-Nas

.gitignore

@@ -1,2 +1,4 @@
 .history
-__pycache__
+__pycache__
+temp.py
+input.txt

leetcode/maxConcatString/maxConcatString.vn.py

@@ -0,0 +1,36 @@
+
+# 1239. Maximum Length of a Concatenated String with Unique Characters
+# https://leetcode.com/problems/maximum-length-of-a-concatenated-string-with-unique-characters
+# Dynamic programming
+# 17/09/2025
+
+def maxLength(self, arr: list[str]) -> int:
+    totalSubsets = 2 ** (len(arr))
+    # dp[mask] = (Mask length with mask, caracs used)
+    for i in range(len(arr)):
+        s = arr[i]
+        arr[i] = 0
+        for carac in s:
+            j = ord(carac) - ord("a")
+            if arr[i] & (1 << j):
+                # strings with duplicates are considered empty
+                arr[i] = 0
+                break
+            arr[i] |= (1 << j)
+
+    dp = [
+        (0, 0) for _ in range(totalSubsets)
+    ]
+
+    for mask in range(totalSubsets):
+        for j in range(len(arr)):
+            if mask == (1 << j):
+                dp[mask] = (arr[j].bit_count(), arr[j])
+            if mask & (1 << j):
+                maskWithoutJ = mask & ~(1 << j)
+                if dp[maskWithoutJ][0] > 0 and (dp[maskWithoutJ][1] & arr[j] == 0):
+                    dp[mask] = (
+                        dp[maskWithoutJ][0] + arr[j].bit_count(),
+                        dp[maskWithoutJ][1] | arr[j]
+                    )
+    return max(dp)[0]

leetcode/maxConcatString/maxConcatString_vis.py

@@ -0,0 +1,86 @@
+
+
+from utils.visualize import AlgorithmVisualizer
+
+class App(AlgorithmVisualizer):
+    def __init__(self, title = "1239. Maximum Length of a Concatenated String with Unique Characters", 
+                 problem_url = "https://leetcode.com/problems/maximum-length-of-a-concatenated-string-with-unique-characters", 
+                 code_url = "https://github.com/Vic-Nas/PythonSolutions/blob/main/leetcode/maxConcatString/maxConcatString.vn.py", 
+                 arr = []
+                 ):
+        self.inp = arr
+        super().__init__(title, problem_url, code_url)
+        
+    def run_algorithm(self):
+        inp = self.inp
+        arr = self.inp.copy()
+        totalSubsets = 2 ** (len(arr))
+        for i in range(len(inp)):
+            s = inp[i]
+            arr[i] = 0
+            for carac in s:
+                j = ord(carac) - ord("a")
+                if arr[i] & (1 << j):
+                    # strings with duplicates are considered empty
+                    arr[i] = 0
+                    break
+                arr[i] |= (1 << j)
+        self.add_step(
+            variables = {
+                "arr": inp,
+                "Converted arr": arr
+            }
+        )
+        
+        dp = [
+        (0, 0) for _ in range(totalSubsets)
+    ]
+        from copy import deepcopy
+        for mask in range(totalSubsets):
+            for j in range(len(arr)):
+                if mask == (1 << j):
+                    dp[mask] = (arr[j].bit_count(), arr[j])
+                if mask & (1 << j):
+                    maskWithoutJ = mask & ~(1 << j)
+                    if dp[maskWithoutJ][0] > 0 and (dp[maskWithoutJ][1] & arr[j] == 0):
+                        dp[mask] = (
+                            dp[maskWithoutJ][0] + arr[j].bit_count(),
+                            dp[maskWithoutJ][1] | arr[j]
+                        )
+                included = [inp[i] for i in range(len(inp)) if mask & (1 << i)]
+                step = (j, inp[j])
+                maskSaved = (f"{mask:0{len(arr)}b}"[::-1], included)
+                dpSaved = [
+                    (x, "".join(c for c in "abcdefghijklmnopqrstuvwxyz" if y & (1 << "abcdefghijklmnopqrstuvwxyz".index(c)))) for x, y in dp
+                ]
+                inpSaved = deepcopy(inp)
+                self.add_step(
+                    variables = {
+                        "inp": inpSaved,
+                        "mask": maskSaved,
+                        "j": step,
+                        "dp": dpSaved,
+                    },
+                    highlight = [mask],
+                    notToHighlight = [maskSaved, step, inpSaved]
+                )
+        dpSaved = [
+                    (x, "".join(c for c in "abcdefghijklmnopqrstuvwxyz" if y & (1 << "abcdefghijklmnopqrstuvwxyz".index(c)))) for x, y in dp
+                ]
+        res = max(dp)[0]
+        self.add_step(
+            variables = {
+                "final dp": dpSaved,
+                "res = max(dp)[0]": res
+            }
+        )
+        return res
+    
+    def get_complexity(self):
+        return {
+            "time": "O(n * 2^n)",
+            "space": "O(2^n)"
+        }
+
+
+App(arr = ["cha","r","act","ers"]).show()

leetcode/nonCoprimes/nonCoprimes.vn.py

@@ -1,4 +1,8 @@
 
+# 2197. Replace Non-Coprime Numbers in Array
+# https://leetcode.com/problems/replace-non-coprime-numbers-in-array
+# Double-linked list
+# 16/09/2025
 
 def replaceNonCoprimes(self, nums: list[int]) -> list[int]:
     from functools import cache

leetcode/nonCoprimes/nonCoprimes_vis.py

@@ -48,7 +48,7 @@ def ppcm(a, b): return a * b // pgcd(a, b)
 class App(AlgorithmVisualizer):
     def __init__(self, title = "Replace Non-Coprime Numbers in Array", 
                  desc = "",
-                 problem_url = "https://leetcode.com/problems/replace-non-coprime-numbers-in-array/description/",
+                 problem_url = "https://leetcode.com/problems/replace-non-coprime-numbers-in-array",
                  code_url = "https://github.com/Vic-Nas/PythonSolutions/blob/main/leetcode/nonCoprimes/nonCoprimes.vn.py",
                  nums = []):
         self.res = DoubleLinkedList(nums)

utils/visualize.py

@@ -123,7 +123,8 @@ def add_step(self,
                  variables: Dict[str, Any], 
                  message: str = "",
                  highlight: List[int] = None,
-                 current: List[int] = None):
+                 current: List[int] = None,
+                 notToHighlight = []):
         """
         Save a step in your algorithm for visualization.
         
@@ -160,9 +161,10 @@ def add_step(self,
         step_data = {
             'variables': variables.copy(),
             'message': message,
-            'highlight': highlight.copy(),
+            'highlight': highlight,
             'current': current.copy(),
-            'step_number': len(self.steps)
+            'step_number': len(self.steps),
+            "notToHighlight": notToHighlight,
         }
         self.steps.append(step_data)
 
@@ -220,7 +222,7 @@ def save(self, filename: str) -> str:
         print(f"💾 Visualization saved to {filename}")
         return filename
 
-    def _render_variable(self, name: str, value: Any, highlight: List[int] = None, current: List[int] = None) -> str:
+    def _render_variable(self, name: str, value: Any, highlight: List[int] = None, current: List[int] = None, notToHighlight = []) -> str:
         """Convert a variable to HTML representation."""
         if highlight is None:
             highlight = []
@@ -229,7 +231,7 @@ def _render_variable(self, name: str, value: Any, highlight: List[int] = None, c
 
         # Handle different data types
         if isinstance(value, (list, tuple)):
-            return self._render_array(name, value, highlight, current)
+            return self._render_array(name, value, highlight if value not in notToHighlight else [], current)
         elif isinstance(value, dict):
             return self._render_dict(name, value)
         elif isinstance(value, (int, float, str, bool)):
@@ -295,7 +297,7 @@ def _generate_html(self) -> str:
             # Render all variables in this step
             variables_html = []
             for var_name, var_value in step['variables'].items():
-                var_html = self._render_variable(var_name, var_value, step['highlight'], step['current'])
+                var_html = self._render_variable(var_name, var_value, step['highlight'], step['current'], notToHighlight=step['notToHighlight'])
                 variables_html.append(var_html)
 
             js_steps.append({