t(n)=√nt(√n)+n
using recurence tree method
every time our main problem goes decreases to n->n1/2->n1/4......n1/2^k
nd cost of reduction for size k is √k where k is a function of n
so after how much time our subproblem becom of size 1 0r 2 i mean when cost becomes constant
.n1/2^k=2 k=loglogn
here cost at each level is same at each level bcoz our main problem is uniformally divided =n
so total cost using recurence tree method =
no of levels*cost at each level = loglogn * n=nloglogn
Ans=θ(nloglogn)