Implement undirected graph and directed graph separately

Author: free-free

python/31_bfs_dfs/graph.py

@@ -0,0 +1,75 @@
+# -*- coding:utf-8 -*-
+
+
+class Undigraph(object):
+
+
+    def __init__(self, vertex_num):
+        self.v_num = vertex_num
+        self.adj_tbl = []
+        for i in range(self.v_num + 1):
+            self.adj_tbl.append([])
+
+    def add_edge(self, s, t):
+        if s > self.v_num or t > self.v_num:
+            return False
+        self.adj_tbl[s].append(t)
+        self.adj_tbl[t].append(s)
+        return True
+    
+    def __len__(self):
+        return self.v_num
+
+    def __getitem__(self, ind):
+        if ind > self.v_num:
+            raise IndexError("No Such Vertex!")
+        return self.adj_tbl[ind]
+
+    def __repr__(self):
+        return str(self.adj_tbl)
+
+    def __str__(self):
+        return str(self.adj_tbl)
+
+
+class Digraph(object):
+
+
+    def __init__(self, vertex_num):
+        self.v_num = vertex_num
+        self.adj_tbl = []
+        for i in range(self.v_num + 1):
+            self.adj_tbl.append([])
+    
+    def add_edge(self, frm, to):
+        if frm > self.v_num or to > self.v_num:
+            return False
+        self.adj_tbl[frm].append(to)
+
+    def __len__(self):
+        return self.v_num
+
+    def __getitem__(self, ind):
+        if ind > self.v_num:
+            raise IndexError("No such vertex!")
+        return self.ajd_tbl[ind]
+
+    def __repr__(self):
+        return str(self.adj_tbl)
+
+    def __str__(self):
+        return str(self.adj_tbl)
+
+
+if __name__ == '__main__':
+    ug = Undigraph(10)
+    ug.add_edge(1, 9)
+    ug.add_edge(1, 3)
+    ug.add_edge(3, 2)
+    print(ug.adj_tbl)
+    
+    dg = Digraph(10)
+    dg.add_edge(1, 9)
+    dg.add_edge(1, 3)
+    dg.add_edge(3, 4)
+    print(dg.adj_tbl)