杨辉三角描述：

1. if m == 1: f(m,n) = n;
2. if n == 1: f(m,n) = m;
3. if m > 1, n >1: f(m,n) = f(m-1,n) + f(m,n -1);

递归算法实现：

unsigned int YHTriple(const unsigned int m, const unsigned int n)
{
	if (m == 1)
		return n;
	
	if (n == 1)
		return m;

	return YHTriple(m-1,n)+YHTriple(m,n-1); 

}

非递归算法实现：

#include<string>
unsigned  int YHTripleNotRecursion(const unsigned int m, const unsigned int n)
{
	std::vector<unsigned int> countTmp;
	for (int i = 1; i <= m; i++)
	{
		std::vector<unsigned int> tmp;
		for (int j = 1; j <= n; j++)
		{
			if (i == 1)
			{
				tmp.push_back(j);
				continue;
			}
			else if (j == 1)
			{
				tmp.push_back(i);
				continue;
			}
			tmp.push_back(tmp[j - 2] + countTmp[j-1]);
		}
		countTmp = tmp;
	}
	return countTmp[countTmp.size() -1];
}