Use a recursion tree for the following algorithms to find th
     Use a recursion tree for the following algorithms to find the running time.  T(n) = T(n - 1) + n  T(n) = 2T(n/3) + n^2 
  
  Solution
2)2T(n/3)+n^2
Subproblem size at level i = n/3i
At level i:Cost of each node=c(n/3i)2
# of nodes=2i Total cost= n2(2/9)i
h=height of the tree ->log3n
Therefore,T(n)=O(n2)

