add some codes

codes/dqn/model.py

@@ -0,0 +1,30 @@
+#!/usr/bin/env python
+# coding=utf-8
+'''
+@Author: John
+@Email: johnjim0816@gmail.com
+@Date: 2020-06-12 00:47:02
+@LastEditor: John
+@LastEditTime: 2020-06-14 11:23:04
+@Discription: 
+@Environment: python 3.7.7
+'''
+import torch.nn as nn
+import torch.nn.functional as F
+
+class FCN(nn.Module):
+    def __init__(self, n_states=4, n_actions=18):
+        """
+        Initialize a deep Q-learning network for testing algorithm
+            n_states: number of features of input.
+            n_actions: number of action-value to output, one-to-one correspondence to action in game.
+        """
+        super(FCN, self).__init__()
+        self.fc1 = nn.Linear(n_states, 128)
+        self.fc2 = nn.Linear(128, 128)
+        self.fc3 = nn.Linear(128, n_actions)
+        
+    def forward(self, x):
+        x = F.relu(self.fc1(x))
+        x = F.relu(self.fc2(x))
+        return self.fc3(x)