Given a non-negative integer numRows, generate the first numRows of Pascal's triangle.
In Pascal's triangle, each number is the sum of the two numbers directly above it.
Example:
c
代码语言：javascript复制class Solution {
public:
vector<vector<int>> generate(int numRows) {
vector<vector<int> > triangle;
int j=1;
for(int i=0;i<numRows;i )
{
vector<int> a;
for(int k=0;k<j;k )
{
if(k==0||k==j-1)
a.push_back(1);
else
a.push_back(triangle[i-1][k] triangle[i-1][k-1]);
}
j ;
triangle.push_back(a);
}
return triangle;
}
};
