204. Count Primes

LeetCodeArrayMathEnumerationNumber TheoryOpen on judge ↗

Given an integer n, return the number of prime numbers that are strictly less than n. Example 1: Input: n = 10 Output: 4 Explanation: There are 4 prime numbers less than 10, they are 2, 3, 5, 7. Example 2: Input: n = 0 Output: 0 Example 3: Input: n = 1 Output: 0 Constraints: - 0 <= n <= 5 * 106

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solution.cppC++17

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