Help - Syntax of Configuration

The systax of configuration description is :
 

NodesNum  = 7   ModulesNum = 8 
InputNode = 1   OutputNode = 5 

The node pair for each module:
A = (1, 2)    --->  module A is located from node 1 to node 2
B = (2, 3)    --->  module B is located from node 2 to node 3
C = (3, 4)    --->  module C is located from node 3 to node 4
D = (3, 4)    --->  module D is located from node 3 to node 4
E = (1, 6)    --->  module E is located from node 1 to node 6
F = (6, 7)    --->  module F is located from node 6 to node 7
G = (7, 4)    --->  module G is located from node 7 to node 4
H = (4, 5)    --->  module H is located from node 4 to node 5

This configuration descripes the system below:
There are 8 modules and 7 nodes in this system. Node 1 is the system input and node 5 is the system output.

If it reports that there is an error in your configuration, please make sure that:

(1): NodesNum>=2 and NodesNum<=20.
(2): ModulesNum>=1 and ModulesNum<=20.
(3): InputNode is between 1 and NodesNum.
(4): OutputNodes is between 1 and NodesNum.
(5): InputNode does not equal OutputNode.
(6): Check whether the Module name and node pairs are legible.
(7): Check whether the syntax is right.
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