APS - Amazing Prime Sequence
Bablu is very fond of Series and Sequences...
After studying Fibonacci Series in Class IX, he was impressed and he designed his own sequence as follows...
a = a = 0
For n > 1, a[n] = a[n - 1] + f(n), where f(n) is smallest prime factor of n.
He is also very fond of programming and thus made a small program to find a[n], but since he is in Class IX, he is not very good at programming. So, he asks you for help. Your task is to find a[n] for the above sequence....
Your code will be checked for multiple Test Cases.
First Line of Input contains T (<= 100), the number of Test Cases.
Next T lines contain a single number N. (1 < N < 10^7).
Single line containing a[n] i.e. nth number of the sequence for each test case.
Input: 3 2 3 4 Output: 2 5 7
nD here 100th completed with such a nice ques !!! modified sieve + precomputation . :)
My code is working fine on codeblocks but gives SIGSEGV error, here on spoj. HELP!!
Precompute using Prime Sieve and O(1) retrieval B| TLE->TLE->WA->AC
why is it showing run time error???
got accepted using sieve and noting down the first prime divisor for each number inside sieve function...nice question though :DLast edit: 2016-05-16 19:08:26
Ray Brish Bhanu:
learned diff b/w declaring an array locally and globally
good problem to learn application of sieve.Precomputation is necessary i think
worked even with long long int!!
easy one! my half century complete..................!!!!!!