add package problems

problems/problem.py

@@ -0,0 +1,15 @@
+class Problem:
+    def __init__(self, forward_way, num_inputs, num_outputs, batch):
+        self.forward_way = forward_way
+        self.batch = batch
+        self.num_inputs = num_inputs
+        self.num_outputs = num_outputs
+
+    def refactor_config(self, config):
+        config.basic.forward_way = self.forward_way
+        config.basic.num_inputs = self.num_inputs
+        config.basic.num_outputs = self.num_outputs
+        config.basic.problem_batch = self.batch
+
+    def evaluate(self, batch_forward_func):
+        pass