Number of pairs with gcd = d https://discuss.codechef.com/questions/73360/puppygcd-editorial Good contest to do: Hello 2015 https://discuss.codechef.com/questions/48877/data-structures-and-algorithms
Number of pairs with gcd = d https://discuss.codechef.com/questions/73360/puppygcd-editorial Good contest to do: Hello 2015 https://discuss.codechef.com/questions/48877/data-structures-and-algorithms