Python implementation of Graph Coloring Problem

greedy_methods/graph_coloring.py

@@ -0,0 +1,48 @@
+import doctest
+
+
+def graph_coloring(graph: list[list[int]]) -> list[int]:
+    """
+    Graph coloring algorithm using a greedy approach.
+
+    Parameters:
+    - graph (List[List[int]])
+
+    Returns:
+    - list[int]
+
+    Example:
+    >>> graph_coloring([[1, 2, 3], [0, 2], [0, 1, 3], [0, 2]])
+    [0, 1, 2, 1]
+
+    >>> graph_coloring([[1], [0, 2], [1]])
+    [0, 1, 0]
+    """
+
+    num_vertices = len(graph)
+    result = [-1] * num_vertices
+    result[0] = 0
+    available_colors = [True] * num_vertices
+
+    for u in range(1, num_vertices):
+        for i in graph[u]:
+            if result[i] != -1:
+                available_colors[result[i]] = False
+
+        cr = 0
+        while cr < num_vertices:
+            if available_colors[cr]:
+                break
+            cr += 1
+
+        result[u] = cr
+
+        for i in graph[u]:
+            if result[i] != -1:
+                available_colors[result[i]] = True
+
+    return result
+
+
+if __name__ == "__main__":
+    doctest.testmod()

scripts/validate_filenames.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python3
+#!/usr/bin/env python
 import os
 
 try: