How can we find second maximum from array efficiently?

Question

Is it possible to find the second maximum number from an array of integers by traversing the array only once?

As an example, I have a array of five integers from whi

Answer 1

Check this solution.

max1 = a[0];
max2 = a[1];

for (i = 1; i < n; i++)
{
    if (max1 < a[i])
    {
        max2 = max1;
        max1 = a[i];
    }

    if (max2 == max1) max2 = a[i + 1];

    if (max2 == a[n])
    {
        printf("All numbers are the same no second max.\n");
        return 0;
    }

    if (max2 < a[i] && max1 != a[i]) max2 = a[i];
}