杨辉三角，原来做过的，开心orz

class Solution {
public:
vector<vector<int>> generate(int numRows) 
{
	vector<vector<int>>res;
	for (int i = 0; i < numRows; i++)
	{
		res.push_back(vector<int>(i+1,1));
	}
	for (int i = 2; i < numRows; i++)
	{
		for (int j = 1; j < i; j++)
		{
			res[i][j] = res[i - 1][j] + res[i-1][j-1];
		}
	}
	return res;
}
};

玄学的内存doge