https://codeforces.com/contest/1299/problem/A
Please can u give me some hint for solving thisproblem
Doubt on greedy bitmasking
@Somasree the key observation in this question is
f(a,b)=(a&(~b))
using this you can module the function on the whole array as
f(a1,an)=(a1&(~a2)&(~a3)…(~an))
now only the first position matters and so we place every element at first and then calculate the ans in o(1)
by pre calculating the prefix and suffix array for( ~a[i]) of values
like pref[i]=(~a[0]&~a[1]&…~a[i])
and reverse for suffix
then we check for each pos and the pos from thich the ans is max then we swap that position and a[0]
the answer at each position is pref[i] & a[i]& suf[i+1]
Coding Blocks IDE
this is the implemented code if not clear let me know
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