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https://www.hackerrank.com/contests/recursion-junior-challenge-2-0/challenges/easy-queries-2

I am unable to solve the question in the above link 

Asked by: Proma_Roy on April 7, 2019, 1:04 p.m. Last updated on April 7, 2019, 1:04 p.m.


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As the subset sum can be greater than or equal to x, first we have to sort the array in decreasing order, then do a prefix sum in another array, say of name, ptr[].

Then store the elements of the ptr in the map(say of name, m), with the ptr elements as 'key' and index (use 1 based indexing) of that element as 'value'.

Then for each query do a lower bound search for x in the map, and print the 'value' of the element which is found. If the search results in m.end(), then print(-1).

Btw, Lower Bound search means searching in the map, till an element greater than or equal to x is encountered.

Be careful, you don't have to print answer for each query, but for each test case as whole.

Samrat_De last updated on April 7, 2019, 1:04 p.m. 0    Reply    Upvote   

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