Solution 1 for Scaler Topics Fortnightly Contest - 22
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Rings with Prime Numbers Complete Solution
This article is part of the Scaler Topics Fortnightly Contest - 22
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Write a function to build an array that holds whether an integer is prime or not, using the sieve of Eratosthenes. Create an array ‘ans’, where ans[i] hold the count of prime numbers for the ith ring.
After observing we can state that there will be only (N/2) rings in case of even N, and (N/2) + 1 in case of an odd value of N. Simply, traverse through all the rings and find the answer.
Time Complexity: O(N*N) Space Complexity: O(N)
C++ Implementation
Java Implementation
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