Add iterable graph with DFS

src/DFS/DFS.py

@@ -0,0 +1,33 @@
+class Graph:
+    def __init__(self, vertices: list[int], edges: list[tuple[int, int]]) -> None:
+        self.vertices = vertices
+        self.edges = edges
+        self.ind = 0
+
+    def dfs_gen(self):
+        states = {"white": [v for v in self.vertices], "gray": list(), "black": list()}
+        visited_verteces = []
+
+        def dfs_step(vertex):
+            if vertex in states["white"]:
+                states["gray"].append(vertex)
+                states["white"].remove(vertex)
+                visited_verteces.append(vertex)
+                for edge in self.edges:
+                    if edge[0] == vertex:
+                        dfs_step(edge[1])
+                    if edge[1] == vertex:
+                        dfs_step(edge[0])
+
+        for vertex in self.vertices:
+            dfs_step(vertex)
+        yield from visited_verteces
+
+    def __iter__(self):
+        return self.dfs_gen()
+
+    # realisation of dfs method that returns list of visited verteces (first subtask)
+    def dfs(self): 
+        return list(self.dfs_gen())
+
+

src/DFS/DFS_test.py

@@ -0,0 +1,40 @@
+from DFS import Graph
+
+def test_graph_iteration():
+    g1 = Graph([0, 1, 2, 3, 4, 5, 6, 7],
+            [(0, 1), (0, 2), (0, 3), (1, 4), (1, 5), (2, 6), (3, 7)])
+    g1l = list(g1)
+    correct_way = [0, 1, 4, 5, 2, 6, 3, 7]
+    assert correct_way == g1l
+
+def test_line_iteration():
+    g2 = Graph([0, 1, 2, 3, 4],
+            [(0, 1), (1, 2), (3, 4)])
+    g2l = list(g2)
+    correct_way = [0, 1, 2, 3, 4]
+    assert correct_way == g2l
+
+def test_single_vertex():
+    g3 = Graph([0],
+            [])
+    g3l = list(g3)
+    assert g3l == [0]
+
+def test_zero_vertex():
+    g4 = Graph([],
+            [])
+    g4l = list(g4)
+    assert g4l == []
+
+def test_dfs():
+    g5 = Graph([0, 1, 2, 3, 4, 5, 6, 7],
+            [(0, 1), (0, 2), (0, 3), (1, 4), (1, 5), (2, 6), (3, 7)])
+    correct_way = [0, 1, 4, 5, 2, 6, 3, 7]
+    assert correct_way == g5.dfs()
+
+
+
+
+
+
+