第一题答案，请指教：
#include <iostream>

using namespace std;

unsigned int getMinEven(int *a, int len, int n)
{
    int res, count;
    res = 0;
    count = 0;
    int tmp = 1;
    while(count != n)
    {
        bool flag = false;
        for(int i = 0; i < len; i++)
        {
            if(a[i] > 0 && a[i] == tmp * 2)
            {
                flag = true;
                break;
            }
        }
        if(flag != true)
        {
            res = tmp * 2;
            count++;
        }
        tmp++;
    }
    return (static_cast<unsigned int>(res));
}

int main(int argc, const char * argv[])
{
    // insert code here...
    int arr[4] = {-1, 2, 2, 3};
    cout << getMinEven(arr, 4, 10) << endl;
    return 0;
}