Composite numbers from 1-10 in c plus plus programming?

Answer 1

#include<iostream>

bool is_composite (const size_t);

bool is_prime (const size_t);

int main()

{

for (size_t num=1; num<=10; ++num)

if (is_composite (num))

std::cout << num << " is composite\n";

}

bool is_composite (const size_t num)

{

if (num < 4U)

return false;

return !is_prime (num);

}

bool is_prime (const size_t num)

{

const size_t two = 2U;

if (num < two)

return false;

if (!(num % two))

return num == two;

const size_t max = static_cast<size_t>(sqrt (static_cast<double>(num)));

for (size_t div = 3U; div <= max; div += two)

if (!(num % div))

return false;

return true;

}