added complete graph generator function

graphs/complete_graph_generator.py

@@ -0,0 +1,33 @@
+"""
+* Author: Manuel Di Lullo (https://github.com/manueldilullo)
+* Python Version: 3.9
+* Description: Complete graphs generator. Uses graphs represented with an adjacency list
+
+URL: https://en.wikipedia.org/wiki/Complete_graph
+"""
+
+
+def complete_graph(vertices_number: int) -> dict:
+    """
+    Generates a complete graph with n vertices
+    @input: n (number of vertices),
+            directed (False if the graph is undirected, True otherwise)
+    @example:
+    >>> print(complete_graph(3))
+    {0: [1, 2], 1: [0, 2], 2: [0, 1]}
+    """
+    g = {}
+    for i in range(vertices_number):
+        g[i] = []
+        for j in range(0, vertices_number):
+            if i != j:
+                g[i].append(j)
+    return g
+
+
+if __name__ == "__main__":
+    import doctest
+
+    doctest.testmod()
+
+    # print(f"Complete graph:\n{complete_graph(5)}")