how to determine maximum route cost in a n high numeric pyramid

Question

I\'ve got a numeric pyramid like this

       7
      4 8
     1 8 9
    2 4 6 7
   4 6 7 4 9
  4 9 7 3 8 8

routes: 32

every number indexed by

Answer 1

as you can Consider the tree a DAG Do a Topological sort then relax(relax to the max not min) each edge as they are in the topological sort O(E+V) .