Given two integers L and R, the task is to find the number of prime numbers in the range [L, R] that can be represented by the sum of two squares of two numbers.
Input: L = 1, R = 5
Only prime number that can be expressed as sum of two perfect squares in the given range is 5 (22 + 12)
Input: L = 7, R = 42
The prime numbers in the given range that can be expressed as sum of two perfect squares are:
13 = 22 + 32
17 = 12 + 42
29 = 52 + 22
37 = 12 + 62
41 = 52 + 42
(p – 1) % 4 == 0
Follow the steps below to solve the problem:
- Traverse the range [L, R].
- For every number, check if it is a prime number of not.
- If found to be so, check if the prime number is of the form 4K + 1. If sp, increase count.
- After traversing the complete range, print count.
Below is the implementation of the above approach:
Time Complexity: O(N3/2)
Auxiliary Space: O(1)
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