int lis(std::vector<int> nums)
{
    int n = nums.size();
    int max = 0, i, j;
    std::vector<int> buf(n, 1);
    for (i = 1; i < n; i++)
        for (j = 0; j < i; j++)
            if (nums[i] > nums[j] && buf[i] < buf[j] + 1)
                buf[i] = buf[j] + 1;

    for (i = 0; i < n; i++)
        if (max < buf[i])
            max = buf[i];

    return max;
}