Print prime numbers in a given range using C++ STL
Generate all prime numbers between two given numbers. The task is to print prime numbers in that range. The Sieve of Eratosthenes is one of the most efficient ways to find all primes smaller than n where n is smaller than 10 million or so. Examples:
Input : start = 50 end = 100 Output : 53 59 61 67 71 73 79 83 89 97 Input : start = 900 end = 1000 Output : 907 911 919 929 937 941 947 953 967 971 977 983 991 997
Idea is to use Sieve of Eratosthenes as a subroutine. Firstly, find primes in the range from 0 to start and store it in a vector. Similarly, find primes in the range from 0 to end and store in another vector. Now take the set difference of two vectors to obtain the required answer. Remove extra zeros if any in the vector.
53 59 61 67 71 73 79 83 89 97
Time Complexity : O(NlogN), where N is the difference between the intervals.
Auxiliary Space : O(N), to store boolean vector.
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