Answer 1

// please input appropriate headers for meh
// m lazy

int array[5];
int sum = 0;
int sum_sqr = 0;
int mean;
int std_dev;

for (int i = 0; i < 5; i++)
{
std::cin >> array[i];
sum += array[i];
sum_sqr += pow(array[i], 2);
}

// Now, we have all 5 values inside the array, their sum and sum of their squares
// proceeding with mean and sd,

mean = sum/5;
std_dev = sqrt((sum_sqr/5)-(pow(mean, 2)));

// after writing these codes, I realise we didn't even need the array lol
// but it's always good to keep a copy of the original data