118. Pascal's Triangle (Graph; WFS)

[
[1],
[1,1],
[1,2,1],
[1,3,3,1],
[1,4,6,4,1]
]

class Solution {
public:
vector<vector<int> > generate(int numRows) {
vector<vector<int>> result(numRows, vector<int>());
if(numRows == 0) return result;
result[0].push_back(1);
for(int i =1; i < numRows; i++) //深度其次
{
result[i].push_back(1);
for(int j = 1; j<i;j++) //广度优先
{
result[i].push_back(result[i-1][j-1]+result[i-1][j]);
}
result[i].push_back(1);
}
return result;
}
};