c++ - What's the complexity of this algorithm -

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• time complexity of primality testing algorithm? 1 answer

what time complexity of algorithm?

void prime(int n) {      int = 2;     while ((n % i) && <= sqrt(n))         i++;      if (i > sqrt(n))         print(“%d prime number\n”, n);     else         print(“%d not prime number\n”, n); } 

the complexity approximately o(sqrt(n)). books express o(n^0.5).

the square root re-computed each iteration of loop. slow operation, it's slower optimal, constant factor, doesn't affect computational complexity.