Create Sieve of Eratosthenes.md

Author: cheatsheet1999

Algorithms/Sieve of Eratosthenes.md

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+```py
+def sieve_of_eratosthenes(n):
+ # Create a boolean array, initialized to True, indicating all numbers are prime
+ is_prime = [True] * (n + 1)
+ p = 2
+ while (p * p <= n):
+ # If is_prime[p] has not been marked as False, it is a prime number
+ if is_prime[p]:
+ # Mark all multiples of p as False, starting from p squared
+ for i in range(p * p, n + 1, p):
+ is_prime[i] = False
+ p += 1
+
+ # Collect all numbers that have not been marked as False, which are prime
+ primes = [p for p in range(2, n + 1) if is_prime[p]]
+ return primes
+
+# Test the algorithm to find all primes less than or equal to 100
+n = 100
+primes = sieve_of_eratosthenes(n)
+print(f"All primes less than or equal to {n}: {primes}")
+
+```
+
+
+