Best way to diagram shortest OSPF Cost Routes?

I'm trying to figure out the west way to diagram the best routes of a network based on costs. Is there a program out there or an excel sheet or something where I put in the devices, connect all of them, put in the costs and it will tell me the route data will flow?

Most importantly, I am looking for a feature where I can change costs of circuits and it will autoupdate and tell me the new best route, dependent on the new costs.

Does anything like this exist? I'm a very visual person so my "ideal" program would be like

Input box 1 : Starting Router

Input box 2: Ending router

Output: Router A -> Router C -> Router B - Cost: 11

[Output Diagram of entire network, but the route taken is highlighted]

Thanks!