题目一：求数组的最大值和次大值

void select_max(const int*a, int size, int&nMax, int& nSecondMax)
{
    nMax = a[0];
    nSecondMax = a[0];
    for (int i = 0; i < size; i++)
    {
        if (nMax < a[i])
        {
            nSecondMax = nMax;
            nMax = a[i];
        }
        else if (nSecondMax < a[i])
        {
            nSecondMax = a[i];
        }
    }
}

题目二：求最大值和最小值

void select_max(const int*a, int size, int&nMax, int& nMin)
{
    nMax = a[0];
    nMin = a[0];
    for (int i = 0; i < size; i++)
    {
        if (nMax < a[i])
        {
            nMax=a[i];
        }
        if (nMin > a[i])
        {
            nMin = a[i];
        }
    }
}