Algorithms Concepts¶
Proof¶
Two steps of correctness proof
- feasibility: satisfy the constraints 
- optimality: better than any other solution 
To prove feasibility, we just check whether the constraints are satisfied. To prove optimality, there are many approaches.
- \(OPT\) gradually approaches out solution \(S\), e.g. by induction 
Say our solution will not overshoot by saying that it is a feasible solution.
Simplification¶
Try to think some reasonable assumptions to transform the original problem setting into a simpler setting. If the optimal solution under the new setting corresponds to an optimal solution under the original setting, then the transformation is valid.
Graph Basics¶
- Forest: a graph that is not connected and have no cycles